Insulin receptor partial agonists

ABSTRACT

Insulin dimers and insulin analog dimers that act as partial agonists at the insulin receptor are disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of U.S. Provisional PatentApplication No. 62/082,857 filed Nov. 21, 2014 and U.S. ProvisionalPatent Application No. 62/242,503 filed Oct. 16, 2015, both of which areherein incorporated by reference in their entirety.

REFERENCE TO SEQUENCE LISTING SUBMITTED ELECTRONICALLY

The sequence listing of the present application is submittedelectronically via EFS-Web as an ASCII formatted sequence listing with afile name “23876_US_NP_SEQLIST_13OCT2015.txt”, creation date of Oct. 13,2015, and a size of 7 Kb. This sequence listing submitted via EFS-Web ispart of the specification and is herein incorporated by reference in itsentirety.

BACKGROUND OF THE INVENTION (1) Field of the Invention

The present invention relates to insulin dimers and insulin analogdimers that act as partial agonists at the insulin receptor.

(2) Description of Related Art

Insulin is an essential therapy for type 1 diabetes mellitus (T1DM)patients and many type 2 mellitus diabetics (T2DMs), prescribed to closeto one third of U.S. patients among all anti-diabetic drug users in thepast decade. The worldwide market for insulins was US$20.4 billion in2013 and is growing at a faster rate than all other anti-diabetic agentscombined. However, challenges of current insulin therapies, includingnarrow TI to hypoglycemia and body weight gain, limit their wideradoption and potential for patients to achieve ideal glycemic control.

In addition to prandial insulin secretion in response to meals, thepancreas releases insulin at a “basal” rate, governed largely by plasmaglucose levels to maintain appropriate fasting glucose regulation. Thisis achieved mainly by controlling hepatic glucose release, throughendogenous insulin's hepato-preferring action. Modern insulin analogsinclude rapid acting and basal insulins, as well as mixtures of thesetwo. Rapid-acting insulin analogs (RAA) are developed to controlpost-prandial hyperglycemia while insulins with extended duration ofaction regulate basal glucose levels. Long-acting insulins are used byall T1DM (in combination with prandial injections) and the majority ofT2DM patients start their insulin therapy from a basal product. Basalinsulin consumption is growing rapidly as the worldwide diabetespopulation (particularly T2DM) soars.

Despite continuous development efforts over the past several decades,available long-acting insulins are still not optimized compared tophysiological basal insulin. This is partially because major focus wason improving PK flatness of these analogs but not fixing the relativeover-insulinization of peripheral tissues, which contributes toincreased hypoglycemia risk. As a result, hypoglycemia remains a keymedical risk with huge burden on patients and causes significantmorbidity and mortality.

BRIEF SUMMARY OF THE INVENTION

The present invention provides compounds comprising to two insulinmolecules covalently linked to form an insulin molecule dimer that mayactivate the insulin receptor with regular insulin-like potency but withreduced maximum activity. These compounds are insulin receptor partialagonists (IPRAs): they behave like other insulin analogs to lowerglucose effectively but with lower risk of hypoglycemia.

Provided are insulin receptor partial agonist covalent insulin dimersformulated as novel and transformative basal insulins (once dailyadministration) that manifest an improved therapeutic index (TI) overcurrent standard of care (SOC) basal insulins. In one embodiment, theIPRAs of the present invention may lower glucose effectively withreduced risk of hypoglycemia in diabetic minipig and has the property ofa once daily (QD) basal insulin. The improved TI may empowerpractitioners to more aggressively dose IRPAs of the present inventionto achieve target goals for control of fasting glucose. Tight control offasting glucose and HbA1c by an IRPA may allow it to serve as 1) astand-alone long-acting insulin with an enhanced efficacy and safetyprofile in T2DM and 2) an improved foundational basal insulin in T1DM(and some T2DM) for use with additional prandial rapid-acting insulinanalogs (RAA) doses. Thus, the present invention provides the followingembodiments.

The present invention provides an insulin receptor partial agonist orinsulin dimer comprising a first insulin or insulin analog heterodimerand a second insulin or insulin analog heterodimer each heterodimerincluding an A-chain polypeptide and a B-chain polypeptide, wherein theA-chain polypeptide and the B-chain polypeptide are linked togetherthrough interchain disulfide bonds; wherein the first and second insulinor insulin analog heterodimers are covalently linked together through alinking moiety joining the side chain of an amino acid at or near thecarboxy terminus of the two respective B-chain polypeptides; and whereinat least one amino terminus of the A-chain polypeptides and the B-chainpolypeptides is covalently linked to a substituent, with the provisothat the linking moiety does not include a disulfide bond. In particularaspects, at least the amino terminus of the A-chain polypeptide and theB-chain polypeptide of the first insulin or insulin analog arecovalently linked to a substituent.

In particular aspects of the insulin receptor partial agonist or insulindimer, the amino terminus of each A-chain polypeptide and each B-chainpolypeptide is covalently linked to a substituent. In particularaspects, the amino terminus of the A-chain polypeptide and the B-chainpolypeptide of the first insulin or insulin analog and the aminoterminus of the A-chain polypeptide and B-chain polypeptide of thesecond insulin or insulin analog are each covalently linked to asubstituent. In embodiments in which the amino termini of the first andsecond insulin or insulin analogs are covalently linked to asubstituent, the substituent on the amino termini of the A-chain andB-chain polypeptides of the first insulin or insulin analog may be thesame as the substituent on the amino termini of the A-chain and B-chainpolypeptides of the second insulin or insulin analog. In embodiments inwhich the amino termini of the first and second insulin or insulinanalogs are covalently linked to a substituent, the substituent on theamino termini of the A-chain and B-chain polypeptides of the firstinsulin or insulin analog may be different from the sub stituent on theamino termini of the A-chain and B-chain polypeptides of the secondinsulin or insulin analog.

In a further aspect of the insulin receptor partial agonist or insulindimer, the first and second insulin or insulin analog heterodimers arethe same or wherein the first and second insulin or insulin analogheterodimers are different.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the linking moiety covalently links the first insulin orinsulin analog heterodimer and the second insulin or insulin analogheterodimer via the epsilon amino group of a lysine residue at or nearthe carboxy terminus of their respective B-chain polypeptides.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the substituent has a general formula RC(O)—, where R canbe R′CH2, R′NH, R′O, and R′ can be H, linear alkyl chain, amino acid,peptide, PEG, saccharides, which in particular aspects RC(O)— may beacetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl.In particular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In particular aspects of the insulin receptor partial agonist or insulindimer, each A-chain polypeptide independently comprises the amino acidsequence GX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO:3) and each B-chainpolypeptide independently comprises the amino acid sequenceX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX27YTX₃₁X₃₂ (SEQ ID NO:4) orX₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO:5)wherein X₂ is isoleucine or threonine; X₃ is valine, glycine, orleucine; X₈ is threonine or histidine; X₁₇ is glutamic acid orglutamine; X₁₉ is tyrosine, 4-methoxy-phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine; X₂₂ is or phenylalanine anddesamino-phenylalanine; X₂₅ is histidine or threonine; X₂₆ is leucine orglycine; X₂₇ is phenylalanine or aspartic acid; X₂₉ is alanine, glycine,or serine; X₃₀ is histidine, aspartic acid, glutamic acid, homocysteicacid, or cysteic acid; X₃₁ is aspartic acid, proline, or lysine; X₃₂ islysine or proline; X₃₃ is threonine, alanine, or absent; X₃₄ is arginineor absent; and X₃₅ is arginine or absent; with the proviso at least oneof X₃₁ or X₃₂ is lysine.

In particular aspects of the insulin receptor partial agonist or insulindimer, the first and second insulins or insulin analogs areindependently native human insulin, insulin lispro, insulin aspart,desB30 insulin, or insulin glargine.

In particular aspects of the insulin receptor partial agonists orinsulin dimers, the linking moiety may be an optionally substitutedgroup selected from the group consisting of acyl, aliphatic,heteroaliphatic, aryl, heteroaryl, and heterocyclic. The linking moietymay be a bivalent, straight or branched, saturated or unsaturated,optionally substituted C1-C20 hydrocarbon chain wherein one or moremethylene units are optionally and independently replaced by —O—, —S—,—N(R)—, —C(O)—, C(O)O—, OC(O)—, —N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—,—N(R)SO₂—, SO₂N(R)—, a heterocyclic group, an aryl group, or aheteroaryl group, wherein each occurrence of R is independentlyhydrogen, a suitable protecting group, an acyl moiety, arylalkyl moiety,aliphatic moiety, aryl moiety, heteroaryl moiety, or heteroaliphaticmoiety.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the linking moiety is an acyl moiety, —C(O)RC(O)—, whereR is alkyl chain, poly(ethylene glycol) (PEG) chain, amide-containingchain, triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

The present invention further provides an insulin receptor partialagonist or insulin dimer comprising the formula

D¹-L-D²

-   -   wherein D¹ and D² are each independently an insulin or insulin        analog polypeptide, wherein each insulin polypeptide is a        heterodimer comprising an A-chain polypeptide and a B-chain        polypeptide linked together through interchain disulfide bonds;        L is a linking moiety wherein one end of the linker moiety is        attached to an amino acid residue at or near the carboxyl group        of D¹ and the other end of the linker moiety is attached to an        amino acid residue at or near the carboxyl end of D² with the        proviso that L does not include a disulfide linkage; and wherein        the first and second insulin or insulin analog polypeptides        include a substituent attached to the amino terminus of the        A-chain polypeptide and the B-chain polypeptide.

In a further aspect of the insulin receptor partial agonist or insulindimer, D¹ and D² are the same or wherein D¹ and D² are different.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety covalently links D¹ and D² via the epsilonamino group of a lysine residue at or near the carboxy terminus of D¹and D².

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the substituent has a general formula RC(O)—, where R canbe R′CH2, R′NH, R′O, and R′ can be H, linear alkyl chain, amino acid,peptide, PEG, saccharides, which in particular aspects RC(O)— may beacetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl.In particular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In particular aspects of the insulin receptor partial agonist or insulindimer, each A-chain polypeptide independently comprises the amino acidsequence GX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO:3) and each B-chainpolypeptide independently comprises the amino acid sequenceX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX27YTX₃₁X₃₂ (SEQ ID NO:4) orX₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO:5)wherein X₂ is isoleucine or threonine; X₃ is valine, glycine, orleucine; X₈ is threonine or histidine; X₁₇ is glutamic acid orglutamine; X₁₉ is tyrosine, 4-methoxy-phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine; X₂₂ is or phenylalanine anddesamino-phenylalanine; X₂₅ is histidine or threonine; X26 is leucine orglycine; X₂₇ is phenylalanine or aspartic acid; X₂₉ is alanine, glycine,or serine; X₃₀ is histidine, aspartic acid, glutamic acid, homocysteicacid, or cysteic acid; X₃₁ is aspartic acid, proline, or lysine; X₃₂ islysine or proline; X₃₃ is threonine, alanine, or absent; X₃₄ is arginineor absent; and X₃₅ is arginine or absent; with the proviso at least oneof X₃₁ or X₃₂ is lysine.

In a further aspect of the insulin receptor partial agonist or insulindimer, wherein D¹ and D² are independently native human insulin, insulinlispro, insulin aspart, desB30 insulin, or insulin glargine.

In particular aspects of the insulin receptor partial agonists orinsulin dimers, the linking moiety may be an optionally substitutedgroup selected from the group consisting of acyl, aliphatic,heteroaliphatic, aryl, heteroaryl, and heterocyclic. The linking moietymay be a bivalent, straight or branched, saturated or unsaturated,optionally substituted C1-C20 hydrocarbon chain wherein one or moremethylene units are optionally and independently replaced by —O—, —S—,—N(R)—, —C(O)—, C(O)O—, OC(O)—, —N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—,—N(R)SO₂—, SO₂N(R)—, a heterocyclic group, an aryl group, or aheteroaryl group, wherein each occurrence of R is independentlyhydrogen, a suitable protecting group, an acyl moiety, arylalkyl moiety,aliphatic moiety, aryl moiety, heteroaryl moiety, or heteroaliphaticmoiety.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the linking moiety is an acyl moiety, —C(O)RC(O)—, whereR is alkyl chain, poly(ethylene glycol) (PEG) chain, amide-containingchain, triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety is an alkyldioyl, —C(O)(CH₂)_(n)C(O)—, whereinn=0-45, including but not limited to an oxalyl (C2) moiety, a succinyl(C4) moiety, an adipoyl (C6) moiety, a suberyol (C8) moiety, adecanedioyl (C10) moiety, a dodecanedioyl (C12) moiety, atetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16) moiety.

Further provided are compositions comprising any one of theaforementioned insulin receptor partial agonists or insulin dimer and apharmaceutically acceptable carrier.

The present invention further provides an insulin receptor partialagonist or insulin dimer comprising a first insulin or insulin analogheterodimer and a second insulin or insulin analog heterodimer eachheterodimer including an A-chain polypeptide and a B-chain polypeptide,wherein the A-chain polypeptide and the B-chain polypeptide are linkedtogether through interchain disulfide bonds; wherein the first andsecond insulin or insulin analog heterodimers are covalently linkedtogether through a linking moiety joining the side chain of an aminoacid at or near the carboxy terminus of the two respective B-chainpolypeptides; and optionally wherein the amino terminus of at least oneof the A-chain polypeptides and the B-chain polypeptides of the firstinsulin polypeptide or second insulin polypeptide is covalently linkedto a substituent, with the proviso that (1) the linking moiety does notinclude a disulfide bond and (2) when the insulin or insulin analog isnot a human insulin or insulin analog and the amino terminus of theA-chain polypeptide and the B-chain polypeptide do not include asubstituent then the linking moiety is not an oxalyl (C2) moiety, asuberyol (C8) moiety, or a dodecanedioyl (C12) moiety.

In a further aspect of the insulin receptor partial agonist or insulindimer, the first and second insulin or insulin analog heterodimers arethe same or wherein the first and second insulin or insulin analogheterodimers are different.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety covalently links the first insulin or insulinanalog heterodimer and the second insulin or insulin analog heterodimervia the epsilon amino group of a lysine residue at or near the carboxyterminus of their respective B-chain polypeptides.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the substituent has a general formula RC(O)—, where R canbe R′CH2, R′NH, R′O, and R′ can be H, linear alkyl chain, amino acid,peptide, PEG, saccharides, which in particular aspects RC(O)— may beacetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl.In particular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In a further aspect of the insulin receptor partial agonist or insulindimer, the first and second insulins or insulin analogs areindependently native human insulin, insulin lispro, insulin aspart,desB30 insulin, or insulin glargine.

In particular aspects of the insulin receptor partial agonist or insulindimer, each A-chain polypeptide independently comprises the amino acidsequence GX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO:3) and each B-chainpolypeptide independently comprises the amino acid sequenceX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX27YTX₃₁X₃₂ (SEQ ID NO:4) orX₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO:5)wherein X₂ is isoleucine or threonine; X₃ is valine, glycine, orleucine; X₈ is threonine or histidine; X₁₇ is glutamic acid orglutamine; X₁₉ is tyrosine, 4-methoxy-phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine; X₂₂ is or phenylalanine anddesamino-phenylalanine; X₂₅ is histidine or threonine; X26 is leucine orglycine; X₂₇ is phenylalanine or aspartic acid; X₂₉ is alanine, glycine,or serine; X₃₀ is histidine, aspartic acid, glutamic acid, homocysteicacid, or cysteic acid; X₃₁ is aspartic acid, proline, or lysine; X₃₂ islysine or proline; X₃₃ is threonine, alanine, or absent; X₃₄ is arginineor absent; and X₃₅ is arginine or absent; with the proviso at least oneof X₃₁ or X₃₂ is lysine.

In particular aspects of the insulin receptor partial agonists orinsulin dimers, the linking moiety may be an optionally substitutedgroup selected from the group consisting of acyl, aliphatic,heteroaliphatic, aryl, heteroaryl, and heterocyclic. The linking moietymay be a bivalent, straight or branched, saturated or unsaturated,optionally substituted C1-C20 hydrocarbon chain wherein one or moremethylene units are optionally and independently replaced by —O—, —S—,—N(R)—, —C(O)—, C(O)O—, OC(O)—, —N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—,—N(R)SO₂—, SO₂N(R)—, a heterocyclic group, an aryl group, or aheteroaryl group, wherein each occurrence of R is independentlyhydrogen, a suitable protecting group, an acyl moiety, arylalkyl moiety,aliphatic moiety, aryl moiety, heteroaryl moiety, or heteroaliphaticmoiety.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the linking moiety is an acyl moiety, —C(O)RC(O)—, whereR is alkyl chain, poly(ethylene glycol) (PEG) chain, amide-containingchain, triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety is a C2-C20 acyl moiety.

In particular aspects, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

Further provided are compositions comprising any one of theaforementioned insulin receptor partial agonists or insulin dimers and apharmaceutically acceptable carrier.

The present invention further provides an insulin receptor partialagonist or insulin dimer comprising the formula

D¹-L-D²

-   -   wherein D¹ and D² are each independently an insulin or insulin        analog polypeptide, wherein each insulin polypeptide is a        heterodimer comprising an A-chain polypeptide and a B-chain        polypeptide linked together through interchain disulfide bonds;        L is a linking moiety wherein one end of the linker moiety is        attached to an amino acid residue at or near the carboxyl group        of D¹ and the other end of the linker moiety is attached to an        amino acid residue at or near the carboxyl end of D² with the        proviso that L does not include a disulfide linkage; and        optionally, wherein at least one of D¹ or D² includes a        substituent attached to the amino terminus of the A-chain        polypeptide or the B-chain polypeptide of D¹ or D²; with the        proviso that (1) the linking moiety does not include a disulfide        bond and (2) when the amino terminus of the A-chain polypeptide        and the B-chain polypeptide do not include a substituent then        the linking moiety is not an oxalyl (C2) moiety, a suberyol (C8)        moiety, or a dodecanedioyl (C12) moiety.

In a further aspect of the insulin receptor partial agonist or insulindimer, D¹ and D² are the same or wherein D¹ and D² are different.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety covalently links D¹ and D² via the epsilonamino group of a lysine residue at or near the carboxy terminus of D¹and D².

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the substituent has a general formula RC(O)—, where R canbe R′CH2, R′NH, R′O, and R′ can be H, linear alkyl chain, amino acid,peptide, PEG, saccharides, which in particular aspects RC(O)— may beacetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl.In particular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In a further aspect of the insulin receptor partial agonist or insulindimer, D¹ and D² are independently native human insulin, insulin lispro,insulin aspart, desB30 insulin, or insulin glargine.

In particular aspects of the insulin receptor partial agonist or insulindimer, each A-chain polypeptide independently comprises the amino acidsequence GX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO:3) and each B-chainpolypeptide independently comprises the amino acid sequenceX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX27YTX₃₁X₃₂ (SEQ ID NO:4) orX₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO:5)wherein X₂ is isoleucine or threonine; X₃ is valine, glycine, orleucine; X₈ is threonine or histidine; X₁₇ is glutamic acid orglutamine; X₁₉ is tyrosine, 4-methoxy-phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine; X₂₂ is or phenylalanine anddesamino-phenylalanine; X₂₅ is histidine or threonine; X26 is leucine orglycine; X₂₇ is phenylalanine or aspartic acid; X₂₉ is alanine, glycine,or serine; X₃₀ is histidine, aspartic acid, glutamic acid, homocysteicacid, or cysteic acid; X₃₁ is aspartic acid, proline, or lysine; X₃₂ islysine or proline; X₃₃ is threonine, alanine, or absent; X₃₄ is arginineor absent; and X₃₅ is arginine or absent; with the proviso at least oneof X₃₁ or X₃₂ is lysine.

In particular aspects of the insulin receptor partial agonists orinsulin dimers, the linking moiety may be an optionally substitutedgroup selected from the group consisting of acyl, aliphatic,heteroaliphatic, aryl, heteroaryl, and heterocyclic. The linking moietymay be a bivalent, straight or branched, saturated or unsaturated,optionally substituted C1-C20 hydrocarbon chain wherein one or moremethylene units are optionally and independently replaced by —O—, —S—,—N(R)—, —C(O)—, C(O)O—, OC(O)—, —N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—,—N(R)SO₂—, SO₂N(R)—, a heterocyclic group, an aryl group, or aheteroaryl group, wherein each occurrence of R is independentlyhydrogen, a suitable protecting group, an acyl moiety, arylalkyl moiety,aliphatic moiety, aryl moiety, heteroaryl moiety, or heteroaliphaticmoiety.

In a further still aspect of the insulin receptor partial agonist orinsulin dimer, the linking moiety is an acyl moiety, —C(O)RC(O)—, whereR is alkyl chain, poly(ethylene glycol) (PEG) chain, amide-containingchain, triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist or insulindimer, the linking moiety is a C2-C20 acyl moiety.

In particular aspects, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

The present invention further provides an insulin analog dimercomprising:

-   -   a first insulin analog heterodimer and a second insulin or        insulin analog heterodimer each heterodimer including an A-chain        polypeptide and a B-chain polypeptide, wherein the A-chain        polypeptide and the B-chain polypeptide are linked together        through interchain disulfide bonds; wherein the first and second        insulin or insulin analog heterodimers are covalently linked        together through a linking moiety joining the side chain of an        amino acid at or near the carboxy terminus of the two respective        B-chain polypeptides; wherein the insulin analog is selected        from insulin lispro, insulin aspart, and insulin glargine; and        optionally wherein the amino terminus of at least one of the        A-chain polypeptides and the B-chain polypeptides of the first        insulin polypeptide or second insulin polypeptide is covalently        linked to a substituent, with the proviso that the linking        moiety does not include a disulfide bond.

In a further aspect of the insulin receptor partial agonist, the firstand second insulin or insulin analog heterodimers are the same orwherein the first and second insulin or insulin analog heterodimers aredifferent.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety covalently links the first insulin or insulin analog heterodimerand the second insulin or insulin analog heterodimer via the epsilonamino group of a lysine residue at or near the carboxy terminus of theirrespective B-chain polypeptides.

In a further still aspect of the insulin receptor partial agonist, thesubstituent has a general formula RC(O)—, where R can be R′CH2, R′NH,R′O, and R′ can be H, linear alkyl chain, amino acid, peptide, PEG,saccharides, which in particular aspects RC(O)— may be acetyl,phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. Inparticular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In a further aspect of the insulin receptor partial agonist, at leastone of the first and second insulin or insulin analog is furtherconjugated to polyethylene glycol, a sugar moiety, or a heterocycle.

In particular aspects of the insulin receptor partial agonists, thelinking moiety may be an optionally substituted group selected from thegroup consisting of acyl, aliphatic, heteroaliphatic, aryl, heteroaryl,and heterocyclic. The linking moiety may be a bivalent, straight orbranched, saturated or unsaturated, optionally substituted C1-C20hydrocarbon chain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety.

In a further still aspect of the insulin receptor partial agonist, thelinking moiety is an acyl moiety, —C(O)RC(O)—, where R is alkyl chain,poly(ethylene glycol) (PEG) chain, amide-containing chain,triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety is a C2-C20 acyl moiety.

In particular aspects, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

The present invention further provides an insulin analog dimercomprising the formula

D¹-L-D²

-   -   wherein D¹ and D² are each independently an insulin or insulin        analog polypeptide, wherein each insulin polypeptide is a        heterodimer comprising an A-chain polypeptide and a B-chain        polypeptide linked together through interchain disulfide bonds;        L is a linking moiety wherein one end of the linker moiety is        attached to an amino acid residue at or near the carboxyl group        of D¹ and the other end of the linker moiety is attached to an        amino acid residue at or near the carboxyl end of D² with the        proviso that L does not include a disulfide linkage; wherein the        insulin analog is selected from insulin lispro, insulin aspart,        and insulin glargine; and optionally, wherein at least one of D¹        or D² includes a substituent attached to the amino terminus of        the A-chain polypeptide or the B-chain polypeptide of D¹ or D²;        with the proviso that the linking moiety does not include a        disulfide bond.

In a further aspect of the insulin receptor partial agonist, D¹ and D²are the same or wherein D¹ and D² are different.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety covalently links D¹ and D² via the epsilon amino group of alysine residue at or near the carboxy terminus of D¹ and D².

In a further still aspect of the insulin receptor partial agonist, thesubstituent has a general formula RC(O)—, where R can be R′CH2, R′NH,R′O, and R′ can be H, linear alkyl chain, amino acid, peptide, PEG,saccharides, which in particular aspects RC(O)— may be acetyl,phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. Inparticular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In particular aspects of the insulin receptor partial agonists, thelinking moiety may be an optionally substituted group selected from thegroup consisting of acyl, aliphatic, heteroaliphatic, aryl, heteroaryl,and heterocyclic. The linking moiety may be a bivalent, straight orbranched, saturated or unsaturated, optionally substituted C1-C20hydrocarbon chain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety.

In a further still aspect of the insulin receptor partial agonist, thelinking moiety is an acyl moiety, —C(O)RC(O)—, where R is alkyl chain,poly(ethylene glycol) (PEG) chain, amide-containing chain,triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety is a C2-C20 acyl moiety.

In particular aspects, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

The present invention provides an insulin receptor partial agonist,comprising

-   -   a first insulin or insulin analog heterodimer and a second        insulin or insulin analog heterodimer each heterodimer including        an A-chain polypeptide and a B-chain polypeptide, wherein the        A-chain polypeptide and the B-chain polypeptide are linked        together through interchain disulfide bonds; wherein the first        and second insulin or insulin analog heterodimers are covalently        linked together through a linking moiety joining the side chain        of an amino acid at or near the carboxy terminus of the two        respective B-chain polypeptides; optionally wherein the amino        terminus of at least one of the A-chain polypeptides and the        B-chain polypeptides of the first insulin polypeptide or second        insulin polypeptide is covalently linked to a substituent; and        wherein the insulin receptor partial agonist has a maximal        response towards the human insulin receptor (IR) that is about        20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 70% of the        maximal response of native human insulin towards the IR as        determined by a functional phosphorylation assay; or    -   a first insulin or insulin analog heterodimer and a second        insulin or insulin analog heterodimer each heterodimer including        an A-chain polypeptide and a B-chain polypeptide, wherein the        A-chain polypeptide and the B-chain polypeptide are linked        together through interchain disulfide bonds; wherein the first        and second insulin or insulin analog heterodimers are covalently        linked together through a linking moiety joining the side chain        of an amino acid at or near the carboxy terminus of the two        respective B-chain polypeptides; optionally wherein the amino        terminus of at least one of the A-chain polypeptides and the        B-chain polypeptides of the first insulin polypeptide or second        insulin polypeptide is covalently linked to a substituent; and        wherein the insulin receptor partial agonist has a maximal        response towards the human insulin receptor (IR) that is between        20% and 70%, 40% and 70%, 50% and 70%, 40% and 60%, or 20% and        40% of the maximal response of native human insulin towards the        IR as determined by a functional phosphorylation assay; or    -   a first insulin or insulin analog heterodimer and a second        insulin or insulin analog heterodimer each heterodimer including        an A-chain polypeptide and a B-chain polypeptide, wherein the        A-chain polypeptide and the B-chain polypeptide are linked        together through interchain disulfide bonds; wherein the first        and second insulin or insulin analog heterodimers are covalently        linked together through a linking moiety joining the side chain        of an amino acid at or near the carboxy terminus of the two        respective B-chain polypeptides; optionally wherein the amino        terminus of at least one of the A-chain polypeptides and the        B-chain polypeptides of the first insulin polypeptide or second        insulin polypeptide is covalently linked to a substituent; and        wherein the insulin receptor partial agonist has a maximal        response towards the human insulin receptor (IR) that is at        least 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 70%        of the maximal response of native human insulin towards the IR        as determined by a functional phosphorylation assay; or    -   a first insulin or insulin analog heterodimer and a second        insulin or insulin analog heterodimer each heterodimer including        an A-chain polypeptide and a B-chain polypeptide, wherein the        A-chain polypeptide and the B-chain polypeptide are linked        together through interchain disulfide bonds; wherein the first        and second insulin or insulin analog heterodimers are covalently        linked together through a linking moiety joining the side chain        of an amino acid at or near the carboxy terminus of the two        respective B-chain polypeptides; optionally wherein the amino        terminus of at least one of the A-chain polypeptides and the        B-chain polypeptides of the first insulin polypeptide or second        insulin polypeptide is covalently linked to a substituent; and        wherein the insulin receptor partial agonist has a maximal        response towards the human insulin receptor (IR) that is less        than 70% of the maximal response of native human insulin towards        the IR as determined by a functional phosphorylation assay; or    -   a first insulin or insulin analog heterodimer and a second        insulin or insulin analog heterodimer each heterodimer including        an A-chain polypeptide and a B-chain polypeptide, wherein the        A-chain polypeptide and the B-chain polypeptide are linked        together through interchain disulfide bonds; wherein the first        and second insulin or insulin analog heterodimers are covalently        linked together through a linking moiety joining the side chain        of an amino acid at or near the carboxy terminus of the two        respective B-chain polypeptides; optionally wherein the amino        terminus of at least one of the A-chain polypeptides and the        B-chain polypeptides of the first insulin polypeptide or second        insulin polypeptide is covalently linked to a substituent; and        wherein the insulin receptor partial agonist has a maximal        response towards the human insulin receptor (IR) that is about        20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, or 70% of the        maximal response of native human insulin towards the IR as        determined by a functional phosphorylation assay.

In the above embodiments, the functional phosphorylation assay may be anInsulin Receptor (IR) AKT-Phosphorylation assay.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety does not include a disulfide bond and when the amino terminus ofthe A-chain polypeptide and the B-chain polypeptide do not include asubstituent the linking moiety is not an oxalyl (C2) moiety, a suberyol(C8) moiety, or a dodecanedioyl (C12) moiety.

In a further aspect of the insulin receptor partial agonist, the firstand second insulin or insulin analog heterodimers are the same orwherein the first and second insulin or insulin analog heterodimers aredifferent.

In a further aspect of the insulin receptor partial agonist, wherein thelinking moiety covalently links the first insulin or insulin analogheterodimer and the second insulin or insulin analog heterodimer via theepsilon amino group of a lysine residue at or near the carboxy terminusof their respective B-chain polypeptides.

In a further still aspect of the insulin receptor partial agonist, thesubstituent has a general formula RC(O)—, where R can be R′CH2, R′NH,R′O, and R′ can be H, linear alkyl chain, amino acid, peptide, PEG,saccharides, which in particular aspects RC(O)— may be acetyl,phenylacetyl, carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. Inparticular aspects, the substituent is selected from the groupconsisting of acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl,isobutyl, methoxy acetyl, glycine, aminoethylglucose (AEG), AEG-C6,PEG1, PEG2, N-dimethyl, and alkoxycarbonyl.

In a further aspect of the insulin receptor partial agonist, the firstand second insulins or insulin analogs are independently native humaninsulin, insulin lispro, insulin aspart, desB30 insulin, or insulinglargine.

In particular aspects of the insulin receptor partial agonist, eachA-chain polypeptide independently comprises the amino acid sequenceGX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO:3) and each B-chainpolypeptide independently comprises the amino acid sequenceX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX27YTX₃₁X₃₂ (SEQ ID NO:4) orX₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO:5)wherein X₂ is isoleucine or threonine; X₃ is valine, glycine, orleucine; X₈ is threonine or histidine; X₁₇ is glutamic acid orglutamine; X₁₉ is tyrosine, 4-methoxy-phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine; X₂₂ is or phenylalanine anddesamino-phenylalanine; X₂₅ is histidine or threonine; X26 is leucine orglycine; X₂₇ is phenylalanine or aspartic acid; X₂₉ is alanine, glycine,or serine; X₃₀ is histidine, aspartic acid, glutamic acid, homocysteicacid, or cysteic acid; X₃₁ is aspartic acid, proline, or lysine; X₃₂ islysine or proline; X₃₃ is threonine, alanine, or absent; X₃₄ is arginineor absent; and X₃₅ is arginine or absent; with the proviso at least oneof X₃₁ or X₃₂ is lysine.

In particular aspects of the insulin receptor partial agonists, thelinking moiety may be an optionally substituted group selected from thegroup consisting of acyl, aliphatic, heteroaliphatic, aryl, heteroaryl,and heterocyclic. The linking moiety may be a bivalent, straight orbranched, saturated or unsaturated, optionally substituted C1-20hydrocarbon chain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety.

In a further still aspect of the insulin receptor partial agonist, thelinking moiety is an acyl moiety, —C(O)RC(O)—, where R is alkyl chain,poly(ethylene glycol) (PEG) chain, amide-containing chain,triazole(s)-containing chain, cyclooctyne-containing moiety, asubstituted acyl chain, or a polyethylene glycol (PEG) chain.

In a further aspect of the insulin receptor partial agonist, the linkingmoiety is a C2-C20 acyl moiety.

In particular aspects, the linking moiety is an alkyldioyl,—C(O)(CH₂)_(n)C(O)—, wherein n=0-45, including but not limited to anoxalyl (C2) moiety, a succinyl (C4) moiety, an adipoyl (C6) moiety, asuberyol (C8) moiety, a decanedioyl (C10) moiety, a dodecanedioyl (C12)moiety, a tetradecanedioyl (C14) moiety, or a hexadecanedioyl (C16)moiety.

The present invention further provides an insulin dimer comprising afirst B29 or B28 Lys of a first insulin heterodimer molecule having afirst A-chain polypeptide and first B-chain polypeptide and a second B29or B28 Lys of a second insulin heterodimer having a second A-chainpolypeptide and second B-chain polypeptide conjugated together by abifunctional linker selected from the group consisting Linker 1, Linker2, Linker 3, Linker 10, Linker 11, Liner 12, Linker 13, Linker 14,Linker 15, Linker 16, Linker 17, Linker 18, Linker 19, Linker 20, Linker21, Linker 22, Linker 23, Linker 24, Linker 25, Linker 26, Linker 27,Linker 28, Linker 29, Linker 30, Linker 31, Linker 32, Linker 33, Linker34, Linker 35, Linker 36, Linker 37, Linker 38, Linker 39, Linker 40,Linker 41, Linker 42, Linker 43, Linker 44, Linker 45, Linker 46, Linker47, Linker 48, Linker 49, and Linker 50 with the proviso that when thebifunctional linker is Linker 10, Linker 11, Linker 12, Linker 13, orLinker 14, at least one of the first or second A-chain or B-chainpolypeptides is conjugated at its N-terminal amino acid to a substituentor at least the N-terminal amino acids of the first insulin heterodimermolecule are conjugated to a substituent or the N-terminal amino acidsof both the first insulin heterodimer and second insulin heterodimer areconjugated to a substituent.

In particular embodiments, the substituent comprises anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides. Inparticular embodiments, the substituent is a carbamoyl group, acetylgroup, glycine, methyl group, methoxy group, dimethyl group, isobutylgroup, PEG1 group, AEG group, AEG-C6 alkyl group, or PEG2 group.

The present invention further provides an insulin dimer comprising afirst B29 or B28 Lys of a first insulin heterodimer molecule having afirst A-chain polypeptide and first B-chain polypeptide is conjugated toa first linker selected from the group consisting of Linker 5 and Linker7 and a second B29 or B28 Lys of a second insulin heterodimer having asecond A-chain polypeptide and second B-chain polypeptide conjugated toa second linker selected from the group consisting of Linker 4, Linker6, Linker 8, and Linker 9 conjugated together via the first linker andthe second linker.

In a further embodiment, the present invention provides an insulinanalog dimer, comprising a first B29 or B28 Lys of a first insulinheterodimer molecule having a first A-chain polypeptide and firstB-chain polypeptide conjugated to a first linker selected from the groupconsisting of Linker 5 and Linker 7 and a second B29 or B28 Lys of asecond insulin heterodimer having a second A-chain polypeptide andsecond B-chain polypeptide conjugated to a second linker selected fromthe group consisting of Linker 5 and Linker 7, wherein the first andsecond linkers are conjugated together via a bridging linker having astructure

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG25.

In particular embodiments, the substituent comprises anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides. Inparticular embodiments, the substituent is a carbamoyl group, acetylgroup, glycine, methyl group, methoxy group, dimethyl group, isobutylgroup, PEG1 group, AEG group, AEG-C6 alkyl group, or PEG2 group.

In a further rembodiment, the present invention provides an insulinanalog dimer, comprising a first B29 or B28 Lys of a first insulinheterodimer molecule having a first A-chain polypeptide and firstB-chain polypeptide conjugated to a first linker selected from the groupconsisting of Linker 4, Linker 6, Linker 8, and Linker 9 and a secondB29 or B28 Lys of a second insulin heterodimer having a second A-chainpolypeptide and second B-chain polypeptide conjugated to a second linkerselected from the group consisting of Linker 4, Linker 6, Linker 8, andLinker 9, wherein the first and second linkers are conjugated togethervia a bridging linker having a structure

N₃—R—N₃

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG 25.

In particular embodiments, the substituent comprises anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides. Inparticular embodiments, the substituent is a carbamoyl group, acetylgroup, glycine, methyl group, methoxy group, dimethyl group, isobutylgroup, PEG1 group, AEG group, AEG-C6 alkyl group, or PEG2 group.

The present invention further provides compositions comprising any oneof the insulin receptor partial agonists disclosed herein and apharmaceutically acceptable salt.

The present invention provides a method for treating diabetes comprisingadministering to an individual with diabetes a therapeutically effectiveamount of a composition comprising any one of the aforementioned insulinreceptor partial agonists. In particular aspects the diabetes is Type 1diabetes, Type 2 diabetes, or gestational diabetes.

The present invention provides for the use of a composition for thetreatment of diabetes comprising any one of the aforementioned insulinreceptor partial agonists. In particular aspects the diabetes is Type 1diabetes, Type 2 diabetes, or gestational diabetes.

The present invention provides for the use of any one of the insulinreceptor partial agonists disclosed herein for the manufacture of amedicament for the treatment of diabetes. In particular aspects thediabetes is Type 1 diabetes, Type 2 diabetes, or gestational diabetes.

Definitions

Insulin—as used herein, the term means the active principle of thepancreas that affects the metabolism of carbohydrates in the animal bodyand which is of value in the treatment of diabetes mellitus. The termincludes synthetic and biotechnologically derived products that are thesame as, or similar to, naturally occurring insulins in structure, use,and intended effect and are of value in the treatment of diabetesmellitus. The term is a generic term that designates the 51 amino acidheterodimer comprising the A-chain peptide having the amino acidsequence shown in SEQ ID NO: 1 and the B-chain peptide having the aminoacid sequence shown in SEQ ID NO: 2, wherein the cysteine residues apositions 6 and 11 of the A chain are linked in a disulfide bond, thecysteine residues at position 7 of the A chain and position 7 of the Bchain are linked in a disulfide bond, and the cysteine residues atposition 20 of the A chain and 19 of the B chain are linked in adisulfide bond.

Insulin analog or analogue—the term as used herein includes anyheterodimer analogue or single-chain analogue that comprises one or moremodification(s) of the native A-chain peptide and/or B-chain peptide.Modifications include but are not limited to substituting an amino acidfor the native amino acid at a position selected from A4, A5, A8, A9,A10, A12, A13, A14, A15, A16, A17, A18, A19, A21, B1, B2, B3, B4, B5,B9, B10, B13, B14, B15, B16, B17, B18, B20, B21, B22, B23, B26, B27,B28, B29, and B30; deleting any or all of positions B1-4 and B26-30; orconjugating directly or by a polymeric or non-polymeric linker one ormore acyl, polyethylglycine (PEG), or saccharide moiety (moieties); orany combination thereof. As exemplified by the N-linked glycosylatedinsulin analogues disclosed herein, the term further includes anyinsulin heterodimer and single-chain analogue that has been modified tohave at least one N-linked glycosylation site and in particular,embodiments in which the N-linked glycosylation site is linked to oroccupied by an N-glycan. Examples of insulin analogues include but arenot limited to the heterodimer and single-chain analogues disclosed inpublished international application WO20100080606, WO2009/099763, andWO2010080609, the disclosures of which are incorporated herein byreference. Examples of single-chain insulin analogues also include butare not limited to those disclosed in published InternationalApplications WO9634882, WO95516708, WO2005054291, WO2006097521,WO2007104734, WO2007104736, WO2007104737, WO2007104738, WO2007096332,WO2009132129; U.S. Pat. Nos. 5,304,473 and 6,630,348; and Kristensen etal., Biochem. J. 305: 981-986 (1995), the disclosures of which are eachincorporated herein by reference.

The term further includes single-chain and heterodimer polypeptidemolecules that have little or no detectable activity at the insulinreceptor but which have been modified to include one or more amino acidmodifications or substitutions to have an activity at the insulinreceptor that has at least 1%, 10%, 50%, 75%, or 90% of the activity atthe insulin receptor as compared to native insulin and which furtherincludes at least one N-linked glycosylation site. In particularaspects, the insulin analogue is a partial agonist that has less than80% (or 70%) activity at the insulin receptor as does native insulin.These insulin analogues, which have reduced activity at the insulingrowth hormone receptor and enhanced activity at the insulin receptor,include both heterodimers and single-chain analogues.

Single-chain insulin or single-chain insulin analog—as used herein, theterm encompasses a group of structurally-related proteins wherein theA-chain peptide or functional analogue and the B-chain peptide orfunctional analogue are covalently linked by a peptide or polypeptide of2 to 35 amino acids or non-peptide polymeric or non-polymeric linker andwhich has at least 1%, 10%, 50%, 75%, or 90% of the activity of insulinat the insulin receptor as compared to native insulin. The single-chaininsulin or insulin analogue further includes three disulfide bonds: thefirst disulfide bond is between the cysteine residues at positions 6 and11 of the A-chain or functional analogue thereof, the second disulfidebond is between the cysteine residues at position 7 of the A-chain orfunctional analogue thereof and position 7 of the B-chain or functionalanalogue thereof, and the third disulfide bond is between the cysteineresidues at position 20 of the A-chain or functional analogue thereofand position 19 of the B-chain or functional analogue thereof.

Connecting peptide or C-peptide—as used herein, the term refers to theconnection moiety “C” of the α-C-A polypeptide sequence of a singlechain preproinsulin-like molecule. Specifically, in the natural insulinchain, the C-peptide connects the amino acid at position 30 of theB-chain and the amino acid at position 1 of the A-chain. The term canrefer to both the native insulin C-peptide, the monkey C-peptide, andany other peptide from 3 to 35 amino acids that connects the B-chain tothe A-chain thus is meant to encompass any peptide linking the B-chainpeptide to the A-chain peptide in a single-chain insulin analogue (Seefor example, U.S. Published application Nos. 20090170750 and 20080057004and WO9634882) and in insulin precursor molecules such as disclosed inWO9516708 and U.S. Pat. No. 7,105,314.

Amino acid modification—as used herein, the term refers to asubstitution of an amino acid, or the derivation of an amino acid by theaddition and/or removal of chemical groups to/from the amino acid, andincludes substitution with any of the 20 amino acids commonly found inhuman proteins, as well as atypical or non-naturally occurring aminoacids. Commercial sources of atypical amino acids include Sigma-Aldrich(Milwaukee, Wis.), ChemPep Inc. (Miami, Fla.), and GenzymePharmaceuticals (Cambridge, Mass.). Atypical amino acids may bepurchased from commercial suppliers, synthesized de novo, or chemicallymodified or derivatized from naturally occurring amino acids.

Amino acid substitution—as used herein refers to the replacement of oneamino acid residue by a different amino acid residue.

Conservative amino acid substitution—as used herein, the term is definedherein as exchanges within one of the following five groups:

-   -   I. Small aliphatic, nonpolar or slightly polar residues:        -   Ala, Ser, Thr, Pro, Gly;    -   II. Polar, negatively charged residues and their amides:        -   Asp, Asn, Glu, Gln, cysteic acid and homocysteic acid;    -   III. Polar, positively charged residues:        -   His, Arg, Lys; Ornithine (Orn)    -   IV. Large, aliphatic, nonpolar residues:        -   Met, Leu, Ile, Val, Cys, Norleucine (Nle), homocysteine    -   V. Large, aromatic residues:        -   Phe, Tyr, Trp, acetyl phenylalanine

Treat—As used herein, the term “treat” (or “treating”, “treated”,“treatment”, etc.) refers to the administration of an IRPA of thepresent disclosure to a subject in need thereof with the purpose toalleviate, relieve, alter, ameliorate, improve or affect a condition(e.g., diabetes), a symptom or symptoms of a condition (e.g.,hyperglycemia), or the predisposition toward a condition. For example,as used herein the term “treating diabetes” will refer in general tomaintaining glucose blood levels near normal levels and may includeincreasing or decreasing blood glucose levels depending on a givensituation.

Pharmaceutically acceptable carrier—as used herein, the term includesany of the standard pharmaceutical carriers, such as a phosphatebuffered saline solution, water, emulsions such as an oil/water orwater/oil emulsion, and various types of wetting agents suitable foradministration to or by an individual in need. The term also encompassesany of the agents approved by a regulatory agency of the US Federalgovernment or listed in the US Pharmacopeia for use in animals,including humans.

Pharmaceutically acceptable salt—as used herein, the term refers tosalts of compounds that retain the biological activity of the parentcompound, and which are not biologically or otherwise undesirable. Manyof the compounds disclosed herein are capable of forming acid and/orbase salts by virtue of the presence of amino and/or carboxyl groups orgroups similar thereto.

Pharmaceutically acceptable base addition salts can be prepared frominorganic and organic bases. Salts derived from inorganic bases, includeby way of example only, sodium, potassium, lithium, ammonium, calcium,zinc, and magnesium salts. Salts derived from organic bases include, butare not limited to, salts of primary, secondary and tertiary amines.

Pharmaceutically acceptable acid addition salts may be prepared frominorganic and organic acids. Salts derived from inorganic acids includehydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid,phosphoric acid, and the like. Salts derived from organic acids includeacetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid,malic acid, malonic acid, succinic acid, maleic acid, fumaric acid,tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid,methanesulfonic acid, ethanesulfonic acid, p-toluene-sulfonic acid,salicylic acid, and the like.

Effective or therapeutically effective amount—as used herein refers to anontoxic but sufficient amount of an insulin analog to provide thedesired effect. For example one desired effect would be the preventionor treatment of hyperglycemia. The amount that is “effective” will varyfrom subject to subject, depending on the age and general condition ofthe individual, mode of administration, and the like. Thus, it is notalways possible to specify an exact “effective amount.” It is not alwayspossible to determine the optimal effective amount prior toadministration to or by an individual in need thereof. However, anappropriate “effective” amount in any individual case may be determinedby one of ordinary skill in the art using routine experimentation.

Parenteral—as used herein, the term means not through the alimentarycanal but by some other route such as intranasal, inhalation,subcutaneous, intramuscular, intraspinal, or intravenous.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the glucose lowering effect of Dimers 24, 18, and 40compared to RHI when administered to diabetic minipigs at 0.69 nmol/kg.

FIG. 2A shows the results of an Insulin Tolerance Test (ITT) in micecomparing compound A with RHI (Humulin). Compound A was administered ata dose of 72 U/kg and a dose of 300 U/kg and Humulin was administered ata dose of 18 U/kg and a dose of 72 U/kg.

FIG. 2B shows the results of an Insulin Tolerance Test (ITT) in micecomparing compound B with RHI (Humulin). Compound B was administered ata dose of 72 U/kg and a dose of 300 U/kg and Humulin was administered ata dose of 18 U/kg and a dose of 72 U/kg.

FIG. 2C shows the results of an Insulin Tolerance Test (ITT) in micecomparing Dimer 24 with RHI (Humulin). Dimer 24 was administered at adose of 72 U/kg and a dose of 300 U/kg and Humulin was administered at adose of 18 U/kg and a dose of 72 U/kg.

FIG. 2D shows the results of Dimer 55 in an Insulin Tolerance Test (ITT)in mice. Dimer 55 was administered at a dose of 120 nmol/kg and a doseof 300 nmol/kg.

FIG. 2E shows the results of Dimer 58 in an Insulin Tolerance Test (ITT)in mice. Dimer 58 was administered at a dose of 60 nmol/kg and a dose of300 nmol/kg.

FIG. 2F shows the results of Dimer 60 in an Insulin Tolerance Test (ITT)in mice. Dimer 60 was administered at a dose of 72 nmol/kg and a dose of300 nmol/kg.

FIG. 2G shows the results of Dimer 67 in an Insulin Tolerance Test (ITT)in mice. Dimer 67 was administered at a dose of 120 nmol/kg and a doseof 300 nmol/kg.

FIG. 3 shows that Compound A insulin dimer was degrading to insulinmonomers by 2 hour incubation with rat kidney cell membranes (RKCMs)without glutathione (GSH). The % of parent values are semi-quantitativeonly due to potential differences in ionization efficiencies.

FIG. 4 shows that Compound A insulin dimer was degrading to insulinmonomers by 2 hour incubation with rat kidney cell membranes (RKCMs)with glutathione (GSH). The % of parent values are semi-quantitativeonly due to potential differences in ionization efficiencies.

FIG. 5 shows that Dimer 24 lost some A-chain polypeptide but did notdegrade to monomers by 2 hour incubation with rat kidney cell membranes(RKCMs) without glutathione (GSH). The % of parent values aresemi-quantitative only due to potential differences in ionizationefficiencies.

FIG. 6 shows that Dimer 24 lost some A-chain polypeptide but did notdegrade to monomers by 2 hour incubation with rat kidney cell membranes(RKCMs) with glutathione (GSH). The % of parent values aresemi-quantitative only due to potential differences in ionizationefficiencies.

FIG. 7A shows the glucose lowering effect of Dimers 4, 5, 7, 8, and 9compared to RHI when administered to diabetic minipigs at 0.69 nmol/kg.

FIG. 7B shows the glucose lowering effect of Dimers 18, 19, 20, 21, and22 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 7C shows the glucose lowering effect of Dimers 23, 24, 26, 27, and28 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 7D shows the glucose lowering effect of Dimers 29, 32, 37, 38, and39 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 7E shows the glucose lowering effect of Dimers 40, 41, 43, 44, and48 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 7F shows the glucose lowering effect of Dimers 55, 57, 58, 60, and61 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 7G shows the glucose lowering effect of Dimers 62, 64, 67, 69, and71 compared to RHI when administered to diabetic minipigs at 0.69nmol/kg.

FIG. 711 shows the glucose lowering effect of Dimers 72, 77, and 78compared to RHI when administered to diabetic minipigs at 0.69 nmol/kg.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides compounds comprising two insulinmolecules covalently linked to form a covalently-linked insulin dimerthat may activate the insulin receptor with regular insulin-like potencyand reduced maximum activity. These compounds are insulin receptorpartial agonists (IRPA): they behave like other insulin analogs to lowerglucose effectively but with lower risk of hypoglycemia.

Insulin dimers have been disclosed in Brandenburg et al. in U.S. Pat.No. 3,907,763 (1973); Tatnell et al., Biochem J. 216: 687-694 (1983);Shüttler and Brandenburg, Hoppe-Seyler's Z. Physiol. Chem, 363, 317-330,1982; Weiland et al., Proc Natl. Acad. Sci. (USA) 87: 1154-1158 (1990);Deppe et al., Naunyn-Schmiedeberg's Arch Pharmacol (1994) 350:213-217;Brandenburg and Havenith in U.S. Pat. No. 6,908,897(B2) (2005); Knudsenet al., PLOS ONE 7: e51972 (2012); DiMarchi et al in WO2011/159895;DiMarchi et al. in WO 2014/052451; and Herrera et al., WO2014141165.More recently, insulin dimers have been described in Brant—Synthesis andCharacterization of Insulin Receptor Partial Agonists as a Route toImproved Diabetes Therapy, Ph.D. Dissertation, Indiana University (April2015) and Zaykov and DiMarchi, Poster P212—Exploration of the structuraland mechanistic basis for partial agonism of insulin dimers, AmericanPeptide Symposium, Orlando Fla. (June 20-25 (2015). However, theinventors of the instant invention have discovered that the level ofinsulin activity and partial agonist activity of the dimers is afunction of the dimeric structure, the sequence of the insulin analog,the length of the dimerization linker, and the site of dimerization thatconnects the two insulin polypeptides. The inventors have discoveredthat the insulin dimers of the present invention have reduced risk ofpromoting hypoglycemia when administered in high doses than nativeinsulin or other insulin analogs when administered at high doses.

The present invention provides partial agonist covalently-linked insulindimers formulated as a novel and transformative basal insulin (oncedaily administration) that manifests improved therapeutic index (TI)over current standard of care (SOC) basal insulins. These molecules maylower glucose effectively with reduced risk of hypoglycemia in diabeticminipig and have the property of a once daily (QD) basal insulin. Theimproved TI may enable practitioners to more aggressively dose IRPAdimer to achieve target goals for control of fasting glucose. Tightcontrol of fasting glucose and HbA1c may allow these molecules to serveas 1) a stand-alone long-acting insulin with an enhanced efficacy andsafety profile in Type 2 diabetes mellitus (T2DM) and 2) an improvedfoundational basal insulin in Type 1 diabetes mellitus (T1DM) (and someT2DM) for use with additional prandial rapid-acting insulin analogs(RAA) doses.

An ideal long-acting insulin provides continuous control of fastingglucose in diabetics with highly stable and reproducible PK/PD. However,currently available basal insulins, even those with improved stabilityand reproducibility of PK/PD continue to have a narrow therapeutic indexand hypoglycemia incidents increase as glucose levels approacheuglycemia target. This can often lead to underdosing to avoidhypoglycemia. Treatment with an IRPA of the present invention isexpected to alter this efficacy: hypoglycemia relationship byattenuating the rate of change in glucose lowering as dosing isincreased.

Insulin A and B Chains

Disclosed herein are insulin or insulin analog dimers that have insulinreceptor agonist activity. The level of insulin activity of the dimersis a function of the dimeric structure, the sequence of the insulinanalog, the length of the dimerization linker, and the site ofdimerization that connects the two insulin polypeptides. The insulinpolypeptides of the present invention may comprise the native B and Achain sequences of human insulin (SEQ ID NOs: 1 and 2, respectively) orany of the known analogs or derivatives thereof that exhibit insulinagonist activity when linked to one another in a heteroduplex. Suchanalogs include, for example, proteins that having an A-chain and aB-chain that differ from the A-chain and B-chain of human insulin byhaving one or more amino acid deletions, one or more amino acidsubstitutions, and/or one or more amino acid insertions that do notdestroy the insulin activity of the insulin analog.

One type of insulin analog, “monomeric insulin analog,” is well known inthe art. These are fast-acting analogs of human insulin, including, forexample, insulin analogs wherein:

-   -   (a) the amino acyl residue at position B28 is substituted with        Asp, Lys, Leu, Val, or Ala, and the amino acyl residue at        position B29 is Lys or Pro;    -   (b) the amino acyl residues at any of positions B27 and B30 are        deleted or substituted with a nonnative amino acid.

In one embodiment an insulin analog is provided comprising an Aspsubstituted at position B28 (e.g., insulin aspart (NOVOLOG); see SEQ IDNO:9) or a Lys substituted at position 28 and a proline substituted atposition B29 (e.g., insulin lispro (HUMALOG); see SEQ ID NO:6).Additional monomeric insulin analogs are disclosed in Chance, et al.,U.S. Pat. No. 5,514,646; Chance, et al., U.S. patent application Ser.No. 08/255,297; Brems, et al., Protein Engineering, 5:527-533 (1992);Brange, et al., EPO Publication No. 214,826 (published Mar. 18, 1987);and Brange, et al., Current Opinion in Structural Biology, 1:934-940(1991). These disclosures are expressly incorporated herein by referencefor describing monomeric insulin analogs.

Insulin analogs may also have replacements of the amidated amino acidswith acidic forms. For example, Asn may be replaced with Asp or Glu.Likewise, Gln may be replaced with Asp or Glu. In particular, Asn(A18),Asn(A21), or Asp(B3), or any combination of those residues, may bereplaced by Asp or Glu. Also, Gln(A15) or Gln(B4), or both, may bereplaced by either Asp or Glu.

As disclosed herein insulin single chain analogs are provided comprisinga B chain and A chain of human insulin, or analogs or derivativethereof, wherein the carboxy terminus of the B chain is linked to theamino terminus of the A chain via a linking moiety. In one embodimentthe A chain is amino acid sequence GIVEQCCTSICSLYQLENYCN (SEQ ID NO:land the B chain comprises amino acid sequence FVNQHLCGSHLVEALYLVCGERGFFYTPKT (SEQ ID NO: 2) or a carboxy shortened sequencethereof having B30 deleted, and analogs of those sequences wherein eachsequence is modified to comprise one to five amino acid substitutions atpositions corresponding to native insulin positions selected from A5,A8, A9, A10, A14, A15, A17, A18, A21, B1, B2, B3, B4, B5, B9, B10, B13,B14, B20, B22, B23, B26, B27, B28, B29 and B30, with the proviso that atleast one of B28 or B29 is lysine. In one embodiment the amino acidsubstitutions are conservative amino acid substitutions. Suitable aminoacid substitutions at these positions that do not adversely impactinsulin's desired activities are known to those skilled in the art, asdemonstrated, for example, in Mayer, et al., Insulin Structure andFunction, Biopolymers. 2007; 88(5):687-713, the disclosure of which isincorporated herein by reference.

In accordance with one embodiment the insulin analog peptides maycomprise an insulin A chain and an insulin B chain or analogs thereof,wherein the A chain comprises an amino acid sequence that shares atleast 70% sequence identity (e.g., 70%, 75%, 80%, 85%, 90%, 95%) overthe length of the native peptide, with GIVEQCCTSICSLYQLENYCN (SEQ IDNO: 1) and the B chain comprises an amino acid sequence that shares atleast 60% sequence identity (e.g., 60%, 65%, 70%, 75%, 80%, 85%, 90%,95%) over the length of the native peptide, withFVNQHLCGSHLVEALYLVCGERGFFYTPKT (SEQ ID NO: 2) or a carboxy shortenedsequence thereof having B30 deleted.

Additional amino acid sequences can be added to the amino terminus ofthe B chain or to the carboxy terminus of the A chain of the insulinpolypeptides of the present invention. For example, a series ofnegatively charged amino acids can be added to the amino terminus of theB chain, including for example a peptide of 1 to 12, 1 to 10, 1 to 8 or1 to 6 amino acids in length and comprising one or more negativelycharged amino acids including for example glutamic acid and asparticacid. In one embodiment the B chain amino terminal extension comprises 1to 6 charged amino acids. In accordance with one embodiment the insulinpolypeptides disclosed comprise a C-terminal amide or ester in place ofa C-terminal carboxylate on the A chain.

In various embodiments, the insulin analog has an isoelectric point thathas been shifted relative to human insulin. In some embodiments, theshift in isoelectric point is achieved by adding one or more arginine,lysine, or histidine residues to the N-terminus of the insulin A-chainpeptide and/or the C-terminus of the insulin B-chain peptide. Examplesof such insulin polypeptides include ArgM-human insulin,ArgB³¹ArgB³²-human insulin, Gly^(A21)Arg^(B31)Arg^(B32)-human insulin,Arg^(A0)Arg^(B31)Arg^(B32)-human insulin, andArg^(A0)Gly^(A21)Arg^(B31)Arg^(B32)human insulin. By way of furtherexample, insulin glargine (LANTUS; see SEQ ID NOs: 7 and 8) is anexemplary long-acting insulin analog in which Asn^(A21) has beenreplaced by glycine, and two arginine residues have been covalentlylinked to the C-terminus of the B-peptide. The effect of these aminoacid changes was to shift the isoelectric point of the molecule, therebyproducing a molecule that is soluble at acidic pH (e.g., pH 4 to 6.5)but insoluble at physiological pH. When a solution of insulin glargineis injected into the muscle, the pH of the solution is neutralized andthe insulin glargine forms microprecipitates that slowly release theinsulin glargine over the 24 hour period following injection with nopronounced insulin peak and thus a reduced risk of inducinghypoglycemia. This profile allows a once-daily dosing to provide apatient's basal insulin. Thus, in some embodiments, the insulin analogcomprises an A-chain peptide wherein the amino acid at position A21 isglycine and a B-chain peptide wherein the amino acids at position B31and B32 are arginine. The present disclosure encompasses all single andmultiple combinations of these mutations and any other mutations thatare described herein (e.g., Gly^(A21)-human insulin,Gly^(A21)Arg^(B31)-human insulin, A^(rg)B³¹Arg^(B32)-human insulin,Arg^(B31)-human insulin).

In particular aspects of the insulin receptor partial agonists, one ormore amidated amino acids of the insulin analog are replaced with anacidic amino acid, or another amino acid. For example, asparagine may bereplaced with aspartic acid or glutamic acid, or another residue.Likewise, glutamine may be replaced with aspartic acid or glutamic acid,or another residue. In particular, AsnA¹⁸, AsnA²¹, or AsnB³, or anycombination of those residues, may be replaced by aspartic acid orglutamic acid, or another residue. GlnA¹⁵ or GlnB⁴, or both, may bereplaced by aspartic acid or glutamic acid, or another residue. Inparticular aspects of the insulin receptor partial agonists, the insulinanalogs have an aspartic acid, or another residue, at position A21 oraspartic acid, or another residue, at position B3, or both.

One skilled in the art will recognize that it is possible to replace yetother amino acids in the insulin analog with other amino acids whileretaining biological activity of the molecule. For example, withoutlimitation, the following modifications are also widely accepted in theart: replacement of the histidine residue of position B10 with asparticacid (HisB¹⁰ to AspB¹⁰); replacement of the phenylalanine residue atposition B1 with aspartic acid (PheB1 to AspB1); replacement of thethreonine residue at position B30 with alanine (ThrB30 to AlaB30);replacement of the tyrosine residue at position B26 with alanine (TyrB26to AlaB26); and replacement of the serine residue at position B9 withaspartic acid (SerB9 to AspB9).

In various embodiments, the insulin analog has a protracted profile ofaction. Thus, in certain embodiments, the insulin analog may be acylatedwith a fatty acid. That is, an amide bond is formed between an aminogroup on the insulin analog and the carboxylic acid group of the fattyacid. The amino group may be the alpha-amino group of an N-terminalamino acid of the insulin analog, or may be the epsilon-amino group of alysine residue of the insulin analog. The insulin analog may be acylatedat one or more of the three amino groups that are present in wild-typehuman insulin may be acylated on lysine residue that has been introducedinto the wild-type human insulin sequence. In particular aspects of theinsulin receptor partial agonists, the insulin analog may be acylated atposition A1, B1, or both A1 and B1. In certain embodiments, the fattyacid is selected from myristic acid (C₁₄), pentadecylic acid (C₁₅),palmitic acid (C₁₆), heptadecylic acid (C₁₇) and stearic acid (C₁₈).

Examples of insulin analogs can be found for example in publishedInternational Application WO9634882, WO95516708; WO20100080606,WO2009/099763, and WO2010080609, U.S. Pat. No. 6,630,348, and Kristensenet al., Biochem. J. 305: 981-986 (1995), the disclosures of which areincorporated herein by reference). In further embodiments, the in vitroglycosylated or in vivo N-glycosylated insulin analogs may be acylatedand/or pegylated.

In accordance with one embodiment, an insulin analog is provided whereinthe A chain of the insulin peptide comprises the sequenceGIVEQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃ (SEQ ID NO: 3) and the B chain comprisingthe sequence X₂₅LCGX₂₉X₃₀LVEALYLVCGERGFFYTX₃₁X₃₂ (SEQ ID NO: 4) wherein

-   -   X₈ is threonine or histidine;    -   X₁₇ is glutamic acid or glutamine;    -   X₁₉ is tyrosine, 4-methoxy-phenylalanine, or 4-amino        phenylalanine;    -   X₂₃ is asparagine or glycine;    -   X₂₅ is histidine or threonine;    -   X₂₉ is alanine, glycine or serine;    -   X₃₀ is histidine, aspartic acid, glutamic acid, homocysteic        acid, or cysteic acid;    -   X₃₁ is proline or lysine; and    -   X₃₂ is proline or lysine, with the proviso that at least one of        X₃₁ or X₃₂ is lysine.

In a further embodiment, the B chain comprises the sequenceX₂₂VNQX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFFYT-X₃₁X₃₂X₃₃X₃₄X₃₅ (SEQ ID NO: 5)wherein

-   -   X₂₂ is or phenylalanine and desamino-phenylalanine;    -   X₂₅ is histidine or threonine;    -   X₂₉ is alanine, glycine, or serine;    -   X₃₀ is histidine, aspartic acid, glutamic acid, homocysteic        acid, or cysteic acid;    -   X₃₁ is aspartic acid, proline, or lysine;    -   X₃₂ is lysine or proline;    -   X₃₃ is threonine, alanine, or absent;    -   X₃₄ is arginine or absent; and    -   X₃₅ is arginine or absent;

With the proviso at least one of X₃₁ or X₃₂ is lysine.

Linking Moiety

The insulin dimers disclosed herein are formed between a first andsecond insulin polypeptide wherein each insulin polypeptide comprises anA chain and a B chain. The first and second insulin polypeptides may betwo chain insulin analogs (i.e., wherein the A and B chains are linkedonly via inter-chain disulfide bonds between internal cysteine residues)wherein the first and second insulin polypeptides are linked to oneanother to form the dimer by a covalent bond, bifunctional linker, orusing copper(I) catalyzed alkyne-azide cycloaddition (CuAAC) clickchemistry or copper-free click chemistry to link linking moieties on therespective B chains. In accordance with one embodiment the first andsecond insulin polypeptides are linked to one another by a bifunctionallinker joining the side chain of the B28 or B29 lysine of the B chain ofthe first insulin polypeptide to the side chain of the B28 or B29 aminoacid of the B chain of the second insulin polypeptide.

In particular aspects of the insulin receptor partial agonists, thelinking moiety may be an optionally substituted group selected from thegroup consisting of acyl, aliphatic, heteroaliphatic, aryl, heteroaryl,and heterocyclic. The linking moiety may be a bivalent, straight orbranched, saturated or unsaturated, optionally substituted C1-C20hydrocarbon chain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety.

In one embodiment, the linking moiety comprises a PEG linker, a shortlinear polymer of about 2-25 ethylene glycol units or 2, 3, 4, 5, 6, 7,8, 9, 10, 11, 12, 13, 14, 15, 16, or 25 ethylene glycol units andoptionally one or more amino acids. In particular aspects of the insulinreceptor partial agonists, the PEG linker comprises the structure(PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅, (PEG)₆, (PEG)₇, (PEG)₈, (PEG)₉, (PEG)₁₀,(PEG)₁₁, (PEG)₁₂, (PEG)₁₃, (PEG)₁₄, (PEG)₁₅, (PEG)₁₆, or (PEG)₂₅. ThePEG linker may be a bifunctional linker that may be covalentlyconjugated or linked to epsilon amino group of the position B29 or B28lysine residues of the first and second insulin polypeptides. Thestructure of a bifunctional PEG linker conjugated to the epsilon aminogroup of the lysine groups at position B29 or B28 of the first andsecond insulin polypeptides may be represented by the following generalformula

wherein n=1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, or 25and the wavy line indicates the bond between the linker and the epsilonamino group. Methods for conjugating PEG to the epsilon amino group oflysine are well known in the art, see for example, Veronese,Biomaterials 22: 405-417 (2001).

In particular aspects of the insulin receptor partial agonists, PEGlinking moiety conjugating the epsilon amino group of the lysine atposition B29 or B28 of the first insulin polypeptide to the epsilonamino acid of the lysine at position B29 or B28 of the second insulinpolypeptide is

wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises an acyl moietycomprising 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 15, or 16 carbons. Inparticular aspects of the insulin receptor partial agonists, the acylmoiety is a succinyl (4), adipoyl (C6), suberyol (C8), orhexadecanedioyl (C16) moiety. The acyl moiety may comprise abifunctional linker that may be covalently conjugated or linked toepsilon amino group of the position B29 or B28 lysine residues of thefirst and second insulin polypeptides. The structure of a bifunctionalacyl linker conjugated to the epsilon amino group of the lysine group atposition B29 or B28 of the first and second insulin polypeptides may berepresented by the following general formula

wherein n=0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and the wavy linesindicate the bond between the linker and the epsilon amino group of thelysine at position B29 or B28 of the insulin polypeptides.

In particular aspects of the insulin receptor partial agonists, acyllinking moiety conjugating the epsilon amino group of the lysine atposition B29 or B28 of the first insulin polypeptide to the epsilonamino acid of the lysine at position B29 or B28 of the second insulinpolypeptide is

wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In particular aspects of the insulin receptor partial agonists, thebifunctional acyl linker may further include one or two amino acids atone or both termini of the acyl linker. For example, in particularaspects of the insulin receptor partial agonists, the amino acid at oneor both termini of the linker is gamma glutamic acid (γE), which may berepresented by the following general formula

wherein n=0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 and the wavy linesindicate the bond between the linker and the epsilon amino group of thelysine at position B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises an amide-containingalkyl chain bifunctional linker that may be covalently conjugated orlinked to epsilon amino group of the position B29 or B28 lysine residuesof the first and second insulin polypeptides which may be represented bythe following general formula

wherein n=1 or 2, o=1, 2, 3, 4, or 5, and the wavy lines indicate thebond between the linker and the epsilon amino group of the lysine atposition B29 or B28 of the insulin polypeptides. In a particularembodiment, the linking moiety may have the structure

wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises an amide-containingalkyl chain bifunctional linker that may be covalently conjugated orlinked to epsilon amino group of the position B29 or B28 lysine residuesof the first and second insulin polypeptides which may be represented bythe following general formula

wherein n=1, 2, 3, 4, or 5, o=1 or 2, p=1, 2, 3, 4, or 5, and the wavylines indicate the bond between the linker and the epsilon amino groupof the lysine at position B29 or B28 of the insulin polypeptides. In aparticular embodiment, the linking moiety may have the structure

wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises an amide-containingalkyl chain bifunctional linker that may be covalently conjugated orlinked to epsilon amino group of the position B29 or B28 lysine residuesof the first and second insulin polypeptides and which may berepresented by the following general formula

wherein n=1 or 2, o=1, 2, or 3, p=1 or 2, and the wavy lines indicatethe bond between the linker and the epsilon amino group of the lysine atposition B29 or B28 of the insulin polypeptides. In a particularembodiment, the linking moiety may have the structure

wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In particular embodiments, the linking moiety comprises a ringstructure, which provides rigidity to the linking moiety. In particularembodiments, the ring structure comprises a benzyl group or a saturatedor unsaturated alicyclic group having 3, 4, 5, 6, 7, or 8 carbons. Inparticular embodiments, the alicyclic group comprises a cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, cyclopentyl, or cyclooctyl. Inparticular embodiments, the unsaturated alicyclic group (cycloalkane)comprises a cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclohexenyl,cycloheptenyl, or cyclooctenyl group. In particular embodiments, thering structure may further comprise one or more saturated ornonsaturated aliphatic side chains. In particular embodiments, the ringstructure may further comprise one or more aliphatic side chainscomprising one or more heteroatoms. In particular embodiments, theheteroatom is O, S, or N.

In particular embodiments, the ring structure comprises a heteroatom. Inparticular embodiments, the heteroatom may be O, S, or N. In particularembodiments, the ring structure comprises a benzyl group or a saturatedor unsaturated alicyclic group having 3, 4, 5, 6, 7, or 8 carbons inwhich one or more carbons are substituted with a heteroatom selectedfrom N, O, and S. Examples of ring structures that include a heteroatominclude but are not limited to ethylene oxide, ethylenimime,trimethyloxide, furan, tetrhydrofuran, thiphene, pyrrolidine, pyran,piperidine, imidazole, thiazole, dioxane, morpholine, pyrimidine,triazole, thietane, 1,3-diazetine, 2,3-dihydroazete, 1,2-oxathiolane,isoxazole, oxazole, silole, oxepane, thiepine,3,4,5,6-tetrahydro-2H-azepine, 1,4-thiazepine, azocane, and thiocane.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,1 diacylhaving the following general formula

wherein R₁ and R₂ may be same or different wherein R₁ and R₂ areindependently a bond, a saturated or non-saturated C1-C20 or C1-C6 alkylchain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety, poly(ethylene glycol)(PEG) chain PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅, (PEG)₆, (PEG)₇, (PEG)₈,(PEG)₉, (PEG)₁₀, (PEG)₁₁, (PEG)₁₂, (PEG)₁₃, (PEG)₁₄, (PEG)₁₅, (PEG)₁₆,or (PEG)₂ and wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,1 diacylhaving the following general formula

wherein n and o are independently 0, 1, 2, 3, 4, or 5 wherein the wavylines indicate the bond between the linker and the epsilon amino groupof the lysine at position B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

wherein R₁ and R₂ may be same or different wherein R₁ and R₂ areindependently a bond, a saturated or non-saturated C1-C20 or C1-C6 alkylchain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety, poly(ethylene glycol)(PEG) chain PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅, (PEG)₆, (PEG)₇, (PEG)₈,(PEG)₉, (PEG)₁₀, (PEG)₁₁, (PEG)₁₂, (PEG)₁₃, (PEG)₁₄, (PEG)₁₅, (PEG)₁₆,or (PEG)₂ and wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

wherein n and o are independently 0, 1, 2, 3, 4, or 5 wherein the wavylines indicate the bond between the linker and the epsilon amino groupof the lysine at position B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,4 diacylhaving the following general formula

wherein R₁ and R₂ may be same or different wherein R₁ and R₂ areindependently a bond, a saturated or non-saturated C1-C20 or C1-C6 alkylchain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety, poly(ethylene glycol)(PEG) chain PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅, (PEG)₆, (PEG)₇, (PEG)₈,(PEG)₉, (PEG)₁₀, (PEG)₁₁, (PEG)₁₂, (PEG)₁₃, (PEG)₁₄, (PEG)₁₅, (PEG)₁₆,or (PEG)₂ and wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,4 diacylhaving the following general formula

wherein n and o are independently 0, 1, 2, 3, 4, or 5 wherein the wavylines indicate the bond between the linker and the epsilon amino groupof the lysine at position B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

Wherein m, n, and o are each independently 1 or 2; R₁ and R₂ may be sameor different wherein R₁ and R₂ are independently a bond, a saturated ornon-saturated C1-C20 or C1-C6 alkyl chain wherein one or more methyleneunits are optionally and independently replaced by —O—, —S—, —N(R)—,—C(O)—, C(O)O—, OC(O)—, —N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—,—N(R)SO₂—, SO₂N(R)—, a heterocyclic group, an aryl group, or aheteroaryl group, wherein each occurrence of R is independentlyhydrogen, a suitable protecting group, an acyl moiety, arylalkyl moiety,aliphatic moiety, aryl moiety, heteroaryl moiety, or heteroaliphaticmoiety, poly(ethylene glycol) (PEG) chain PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅,(PEG)₆, (PEG)₇, (PEG)₈, (PEG)₉, (PEG)₁₀, (PEG)₁₁, (PEG)₁₂, (PEG)₁₃,(PEG)₁₄, (PEG)₁₅, (PEG)₁₆, or (PEG)₂ and wherein the wavy lines indicatethe bond between the linker and the epsilon amino group of the lysine atposition B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

Wherein m, n, and o are each independently 1 or 2; wherein p and q areindependently 0, 1, 2, 3, 4, or 5 wherein the wavy lines indicate thebond between the linker and the epsilon amino group of the lysine atposition B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

Wherein m, n, and o are each independently 1 or 2; wherein the wavylines indicate the bond between the linker and the epsilon amino groupof the lysine at position B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a cyclohexane-1,4diacyl having the following general formula

and wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a cyclohexane-1,4diacyl having the following general formula

and wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

Wherein m and n are each independently 0, 1, or 2 with the proviso thatboth m and n are not 0; R₁ and R₂ may be same or different wherein R₁and R₂ are independently a bond, a saturated or non-saturated C1-C20 orC1-C6 alkyl chain wherein one or more methylene units are optionally andindependently replaced by —O—, —S—, —N(R)—, —C(O)—, C(O)O—, OC(O)—,—N(R)C(O)—, —C(O)N(R)—, —S(O)—, —S(O)₂—, —N(R)SO₂—, SO₂N(R)—, aheterocyclic group, an aryl group, or a heteroaryl group, wherein eachoccurrence of R is independently hydrogen, a suitable protecting group,an acyl moiety, arylalkyl moiety, aliphatic moiety, aryl moiety,heteroaryl moiety, or heteroaliphatic moiety, poly(ethylene glycol)(PEG) chain PEG)₂, (PEG)₃, (PEG)₄, (PEG)₅, (PEG)₆, (PEG)₇, (PEG)₈,(PEG)₉, (PEG)₁₀, (PEG)₁₁, (PEG)₁₂, (PEG)₁₃, (PEG)₁₄, (PEG)₁₅, (PEG)₁₆,or (PEG)₂ and wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a benzene-1,3 diacylhaving the following general formula

Wherein m and n are each independently 1 or 2; wherein p and q areindependently 0, 1, 2, 3, 4, or 5 wherein the wavy lines indicate thebond between the linker and the epsilon amino group of the lysine atposition B29 or B28 of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a 1,1 diacyl having thefollowing general formula

wherein n is 1, 2, 3, or 4 wherein the wavy lines indicate the bondbetween the linker and the epsilon amino group of the lysine at positionB29 or B28 of the insulin polypeptides. In specific embodiments, the 1,1diacyl may have a structure selected from

(1,1-diacyl-C3; 1,2-diacyl-C4; 1,1-diacyl-C5; and 1,1-diacyl-C6,respectively) wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a 1,2 diacyl having thefollowing general formula

wherein n is 1, 2, 3, or 4 wherein the wavy lines indicate the bondbetween the linker and the epsilon amino group of the lysine at positionB29 or B28 of the insulin polypeptides. In specific embodiments, the 1,2diacyl may have a structure selected from

(1,2-diacyl-C3; 1,2-diacyl-C4; 1,2-diacyl-C5; and 1,2-diacyl-C6,respectively) wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a 1,3 diacyl having thefollowing general formula

wherein n is 1, 2, or 3 wherein the wavy lines indicate the bond betweenthe linker and the epsilon amino group of the lysine at position B29 orB28 of the insulin polypeptides. In specific embodiments, the 1,3 diacylmay have a structure selected from,

(1,3-diacyl-C4; 1,3-diacyl-05; and 1,3-diacyl-C6, respectively) whereinthe wavy lines indicate the bond between the linker and the epsilonamino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a 1,4 diacyl having thefollowing general formula

(1,4-diacyl-C6) wherein the wavy lines indicate the bond between thelinker and the epsilon amino group of the lysine at position B29 or B28of the insulin polypeptides.

In another embodiment, the linking moiety comprises a bifunctionallinker that may be covalently conjugated or linked to epsilon aminogroup of the position B29 or B28 lysine residues of the first and secondinsulin polypeptides which may be represented by a cyclobutyl-1,3 diacylhaving the following general formula

and wherein the wavy lines indicate the bond between the linker and theepsilon amino group of the lysine at position B29 or B28 of the insulinpolypeptides.

In a further aspect of the present invention, the first and secondinsulin polypeptides may be conjugated together using copper-catalyzedAzide-Alkyne Huisgen Cycloaddition (CuAAc), in particular CuAAC clickchemistry. In this aspect, the epsilon amino group of the B29 or B28lysine of the first insulin polypeptide is conjugated to a linker moietyhaving a proximal end and a distal end wherein the proximal end of thelinker moiety is conjugated to the epsilon amino group and the distalcomprises an azide group. In this aspect, the epsilon amino group of theB29 or B28 lysine of the second insulin polypeptide is conjugated to alinker moiety having a proximal end and a distal end wherein theproximal end of the linker moiety is conjugated to the epsilon aminogroup and the distal comprises an alkyne group. In the presence of Cu2+and a reducing agent, the azide and the alkyne groups will form acontiguous linking moiety comprising a triazole moiety. See U.S. Pat.No. 8,129,542, which is incorporated herein in its entirety, for adescription of CuAAC click chemistry.

In particular aspects of the insulin receptor partial agonists, thefirst insulin polypeptide may have conjugated to the epsilon amino groupof the B29 or B28 lysine a linker having the formula

and the second insulin polypeptide may have conjugated to the epsilonamino group of the B29 or B28 lysine a linker having the formula

In the presence of Cu2+ and a reducing agent, the linkers combine toprovide a linking moiety having the structure

In particular aspects of the insulin receptor partial agonists, thefirst insulin polypeptide may have conjugated to the epsilon amino groupof the B29 or B28 lysine a linker having the formula

wherein n=1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 and the second insulinpolypeptide may have conjugated to the epsilon amino group of the B29 orB28 lysine a linker having the formula

wherein n=1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In the presence of Cu2+ anda reducing agent, the linkers combine to provide a linking moiety havingthe structure

wherein each n independently is 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

In a further aspect, both the first insulin polypeptide and the secondinsulin polypeptide may have conjugated to its respective epsilon aminogroup of the B29 or B28 lysine a linker having the formula

wherein each n is independently 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.Conjugation of the linkers to form a linking moiety may be achieved byproviding a molecule (intermediate or bridging linker) having astructure

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG25.

In a further aspect, both the first insulin polypeptide and the secondinsulin polypeptide may have conjugated to its respective epsilon aminogroup of the B29 or B28 lysine a linker having the formula

wherein each n is independently 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.Conjugation of the linkers to form a linking moiety may be achieved byproviding a molecule (intermediate or bridging linker) having astructure

N₃—R—N₃

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG 25.

In particular aspects, the first insulin polymer is conjugated at theepsilon amino group of the B29 or B28 lysine to an azide terminatedlinker as above and the second insulin polypeptide is conjugated at theepsilon amino group of the B29 or B28 lysine to a linker terminated witha cyclooctyne moiety and the linkers are conjugated to form a linkermoiety using copper-free cycloaddition click chemistry. See for example,U.S. Pat. No. 7,807,619, which is incorporated herein in its entirety.

The following table shows exemplary linkers, which may be used toconstruct the dimers of the present invention. The dimers shown comprise2,5-dioxopyrrolidin-1y groups for conjugating to the epsilon amino groupof the B29 or B29 lysine.

Table of Linkers Linker Name 1

C6 + Nc6 2

C6N + C6 + NC6 3

γE-C8-γE 4

Click-1 5

Click-2 6

Click-3 7

Click-4 8

Click-5 9

Click-6 10

C2 11

C4 12

C6 13

C8 14

C16 15

PEG2 16

PEG3 17

PEG4 18

PEG5 19

PEG6 20

PEG7 21

PEG9 22

PEG13 23

PEG25 24

C6-glycine 25

C6-alanine 26

C6-isoleucine 27

C6-leucine 28

C6-valine 29

Dipropyl phenol 30

Trans- cyclohexane 1,4-diacid 31

Cis- cyclohexane 1,4-diacid 32

Tert-butyl- piperidine- tricarb 33

C6N-chloro- 1,3,5-Triazine- NC6 34

Terephthalate 35

isophthalate 36

Heptanedioate 37

1,1-diacyl-C3 38

1,1-diacyl-C4 39

1,1-diacyl-C5 40

1,1-diacyl-C6 41

1,2-diacyl-C3 42

1,2-diacyl-C4 43

1,2-diacyl-C5 44

1,2-diacyl-C6 45

1,3-diacyl-C4 46

1,3-diacyl-C5 47

1,3-diacyl-C6 48

1,4-diacyl- cyclobutyl-C1 49

1,4- cyclohexyl-C1 50

1,4- cyclohexyl-C2Conjugation of a bifunctional linker to the epsilon amino group of thelysine residue at position B29 or B28 of the B-chain polypeptide of twoinsulin or insulin analog molecules to form the insulin dimer linked bya linking moiety may be schematically shown as

wherein the insulin 1 and insulin 2 molecules may be the same ordifferent and the bifunctional linker and resulting and linking moietyfollowing conjugation may have the structure of any linker and resultinglinking moiety disclosed herein.

Modification of Insulin Polypeptides

In some embodiments, at least one of the A-chain polypeptides or B-chainpolypeptides of the insulin receptor partial agonist is modified tocomprise an acyl group. The acyl group can be covalently linked directlyto an amino acid of the insulin polypeptide, or indirectly to an aminoacid of the insulin polypeptide via a spacer, wherein the spacer ispositioned between the amino acid of the insulin polypeptide and theacyl group. The insulin polypeptide may be acylated at the same aminoacid position where a hydrophilic moiety is linked, or at a differentamino acid position. For example, acylation may occur at any positionincluding any amino acid of the A- or B-chain polypeptides as well as aposition within the linking moiety, provided that the activity exhibitedby the non-acylated insulin polypeptide is retained upon acylation.Non-limiting examples include acylation at positions A1 of the A chainand positions position B1 of the B chain.

In one specific aspect of the invention, the first and/or second insulinpolypeptide (or derivative or conjugate thereof) is modified to comprisean acyl group by direct acylation of an amine, hydroxyl, or thiol of aside chain of an amino acid of the insulin polypeptide. In someembodiments, the first and/or second insulin polypeptide is directlyacylated through the side chain amine, hydroxyl, or thiol of an aminoacid. In this regard, an insulin polypeptide may be provided that hasbeen modified by one or more amino acid substitutions in the A- orB-chain polypeptide sequence, including for example at positions A1,A14, A15, B1, B10, or B22 or at any position of the linking moiety withan amino acid comprising a side chain amine, hydroxyl, or thiol.

In some embodiments, the spacer between the first and/or second insulinpolypeptide and the acyl group is an amino acid comprising a side chainamine, hydroxyl, or thiol (or a dipeptide or tripeptide comprising anamino acid comprising a side chain amine, hydroxyl, or thiol). In someembodiments, the spacer comprises a hydrophilic bifunctional spacer. Ina specific embodiment, the spacer comprises an aminopoly(alkyloxy)carboxylate. In this regard, the spacer can comprise, forexample, NH₂(CH₂CH₂O)_(n)(CH₂)_(m)COOH, wherein m is any integer from 1to 6 and n is any integer from 2 to 12, such as, e.g.,8-amino-3,6-dioxaoctanoic acid, which is commercially available fromPeptides International, Inc. (Louisville, Ky.). In one embodiment, thehydrophilic bifunctional spacer comprises two or more reactive groups,e.g., an amine, a hydroxyl, a thiol, and a carboxyl group or anycombinations thereof. In certain embodiments, the hydrophilicbifunctional spacer comprises a hydroxyl group and a carboxylate. Inother embodiments, the hydrophilic bifunctional spacer comprises anamine group and a carboxylate. In other embodiments, the hydrophilicbifunctional spacer comprises a thiol group and a carboxylate.

In some embodiments, the spacer between the first and/or second insulinpolypeptide and the acyl group is a hydrophobic bifunctional spacer.Hydrophobic bifunctional spacers are known in the art. See, e.g.,Bioconjugate Techniques, G. T. Hermanson (Academic Press, San Diego,Calif., 1996), which is incorporated by reference in its entirety. Incertain embodiments, the hydrophobic bifunctional spacer comprises twoor more reactive groups, e.g., an amine, a hydroxyl, a thiol, and acarboxyl group or any combinations thereof. In certain embodiments, thehydrophobic bifunctional spacer comprises a hydroxyl group and acarboxylate. In other embodiments, the hydrophobic bifunctional spacercomprises an amine group and a carboxylate. In other embodiments, thehydrophobic bifunctional spacer comprises a thiol group and acarboxylate. Suitable hydrophobic bifunctional spacers comprising acarboxylate and a hydroxyl group or a thiol group are known in the artand include, for example, 8-hydroxyoctanoic acid and 8-mercaptooctanoicacid.

In accordance with certain embodiments the bifunctional spacer can be asynthetic or naturally occurring amino acid comprising an amino acidbackbone that is 3 to 10 atoms in length (e.g., 6-amino hexanoic acid,5-aminovaleric acid, 7-aminoheptanoic acid, and 8-aminooctanoic acid).Alternatively, the spacer can be a dipeptide or tripeptide spacer havinga peptide backbone that is 3 to 10 atoms (e.g., 6 to 10 atoms) inlength. Each amino acid of the dipeptide or tripeptide spacer attachedto the insulin polypeptide can be independently selected from the groupconsisting of: naturally-occurring and/or non-naturally occurring aminoacids, including, for example, any of the D or L isomers of thenaturally-occurring amino acids (Ala, Cys, Asp, Glu, Phe, Gly, His, Ile,Lys, Leu, Met, Asn, Pro, Arg, Ser, Thr, Val, Trp, Tyr), or any D or Lisomers of the non-naturally occurring amino acids selected from thegroup consisting of: β-alanine (β-Ala), N-α-methyl-alanine (Me-Ala),aminobutyric acid (Abu), α-aminobutyric acid (γ-Abu), aminohexanoic acid(ε-Ahx), aminoisobutyric acid (Aib), aminomethylpyrrole carboxylic acid,aminopiperidinecarboxylic acid, aminoserine (Ams),aminotetrahydropyran-4-carboxylic acid, arginine N-methoxy-N-methylamide, β-aspartic acid (β-Asp), azetidine carboxylic acid,3-(2-benzothiazolyl)alanine, α-tert-butylglycine,2-amino-5-ureido-n-valeric acid (citrulline, Cit), β-Cyclohexylalanine(Cha), acetamidomethyl-cysteine, diaminobutanoic acid (Dab),diaminopropionic acid (Dpr), dihydroxyphenylalanine (DOPA),dimethylthiazolidine (DMTA), γ-Glutamic acid (γ-Glu), homoserine (Hse),hydroxyproline (Hyp), isoleucine N-methoxy-N-methyl amide,methyl-isoleucine (MeIle), isonipecotic acid (Isn), methyl-leucine(MeLeu), methyl-lysine, dimethyl-lysine, trimethyl-lysine,methanoproline, methionine-sulfoxide (Met(O)), methionine-sulfone(Met(O2)), norleucine (Nle), methyl-norleucine (Me-Nle), norvaline(Nva), ornithine (Orn), para-aminobenzoic acid (PABA), penicillamine(Pen), methylphenylalanine (MePhe), 4-Chlorophenylalanine (Phe(4-C1)),4-fluorophenylalanine (Phe(4-F)), 4-nitrophenylalanine (Phe(4-NO2)),4-cyanophenylalanine ((Phe(4-CN)), phenylglycine (Phg),piperidinylalanine, piperidinylglycine, 3,4-dehydroproline,pyrrolidinylalanine, sarcosine (Sar), selenocysteine (Sec),U-Benzyl-phosphoserine, 4-amino-3-hydroxy-6-methylheptanoic acid (Sta),4-amino-5-cyclohexyl-3-hydroxypentanoic acid (ACHPA),4-amino-3-hydroxy-5-phenylpentanoic acid (AHPPA),1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid (Tic),tetrahydropyranglycine, thienylalanine (Thi), U-Benzyl-phosphotyrosine,O-Phosphotyrosine, methoxytyrosine, ethoxytyrosine,O-(bis-dimethylamino-phosphono)-tyrosine, tyrosine sulfatetetrabutylamine, methyl-valine (MeVal), 1-amino-1-cyclohexane carboxylicacid (Acx), aminovaleric acid, beta-cyclopropyl-alanine (Cpa),propargylglycine (Prg), allylglycine (Alg),2-amino-2-cyclohexyl-propanoic acid (2-Cha), tertbutylglycine (Tbg),vinylglycine (Vg), 1-amino-1-cyclopropane carboxylic acid (Acp),1-amino-1-cyclopentane carboxylic acid (Acpe), alkylated3-mercaptopropionic acid, 1-amino-1-cyclobutane carboxylic acid (Acb).In some embodiments the dipeptide spacer is selected from the groupconsisting of: Ala-Ala, β-Ala-β-Ala, Leu-Leu, Pro-Pro, γ-aminobutyricacid-γ-aminobutyric acid, and γ-Glu-γ-Glu.

The first and/or second insulin polypeptide may be modified to comprisean acyl group by acylation of a long chain alkane. In specific aspects,the long chain alkane comprises an amine, hydroxyl, or thiol group (e.g.octadecylamine, tetradecanol, and hexadecanethiol) which reacts with acarboxyl group, or activated form thereof, of the insulin polypeptide.The carboxyl group, or activated form thereof, of the insulinpolypeptide can be part of a side chain of an amino acid (e.g., glutamicacid, aspartic acid) of the insulin polypeptide or can be part of thepeptide backbone.

In certain embodiments, the first and/or second insulin polypeptide ismodified to comprise an acyl group by acylation of the long chain alkaneby a spacer which is attached to the insulin polypeptide. In specificaspects, the long chain alkane comprises an amine, hydroxyl, or thiolgroup which reacts with a carboxyl group, or activated form thereof, ofthe spacer. Suitable spacers comprising a carboxyl group, or activatedform thereof, are described herein and include, for example,bifunctional spacers, e.g., amino acids, dipeptides, tripeptides,hydrophilic bifunctional spacers and hydrophobic bifunctional spacers.As used herein, the term “activated form of a carboxyl group” refers toa carboxyl group with the general formula R(C═O)X, wherein X is aleaving group and R is the insulin polypeptide or the spacer. Forexample, activated forms of a carboxyl groups may include, but are notlimited to, acyl chlorides, anhydrides, and esters. In some embodiments,the activated carboxyl group is an ester with an N-hydroxysuccinimide(NHS) leaving group.

With regard to these aspects of the invention, in which a long chainalkane is acylated by the peptide, the insulin polypeptide or thespacer, the long chain alkane may be of any size and can comprise anylength of carbon chain. The long chain alkane can be linear or branched.In certain aspects, the long chain alkane is a C₄ to C₃₀ alkane. Forexample, the long chain alkane can be any of a C₄ alkane, C₆ alkane, C₈alkane, C₁₀ alkane, C₁₂ alkane, C₁₄ alkane, C₁₆ alkane, C₁₈ alkane, C₂₀alkane, C₂₂ alkane, C₂₄ alkane, C₂₆ alkane, C₂₈ alkane, or a C₃₀ alkane.In some embodiments, the long chain alkane comprises a C₈ to C₂₀ alkane,e.g., a C₁₄ alkane, C₁₆ alkane, or a C₁₈ alkane.

In some embodiments, an amine, hydroxyl, or thiol group of the firstand/or second insulin polypeptide is acylated with a cholesterol acid.In a specific embodiment, the peptide is linked to the cholesterol acidthrough an alkylated des-amino Cys spacer, i.e., an alkylated3-mercaptopropionic acid spacer. Suitable methods of peptide acylationvia amines, hydroxyls, and thiols are known in the art. See, forexample, Miller, Biochem Biophys Res Commun 218: 377-382 (1996);Shimohigashi and Stammer, Int J Pept Protein Res 19: 54-62 (1982); andPreviero et al., Biochim Biophys Acta 263: 7-13 (1972) (for methods ofacylating through a hydroxyl); and San and Silvius, J Pept Res 66:169-180 (2005) (for methods of acylating through a thiol); BioconjugateChem. “Chemical Modifications of Proteins: History and Applications”pages 1, 2-12 (1990); Hashimoto et al., Pharmacuetical Res. “Synthesisof Palmitoyl Derivatives of Insulin and their Biological Activity” Vol.6, No: 2 pp. 171-176 (1989).

The acyl group of the acylated peptide the first and/or second insulinpolypeptide can be of any size, e.g., any length carbon chain, and canbe linear or branched. In some specific embodiments of the invention,the acyl group is a C₄ to C₃₀ fatty acid. For example, the acyl groupcan be any of a C₄ fatty acid, C₆ fatty acid, C₈ fatty acid, C₁₀ fattyacid, C₁₂ fatty acid, C₁₄ fatty acid, C₁₆ fatty acid, C₁₈ fatty acid,C₂₀ fatty acid, C₂₂ fatty acid, C₂₄ fatty acid, C₂₆ fatty acid, C₂₈fatty acid, or a C₃₀ fatty acid. In some embodiments, the acyl group isa C₈ to C₂₀ fatty acid, e.g., a C₁₄ fatty acid or a C₁₆ fatty acid. Insome embodiments, the acyl group is urea.

In an alternative embodiment, the acyl group is a bile acid. The bileacid can be any suitable bile acid, including, but not limited to,cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid,taurocholic acid, glycocholic acid, and cholesterol acid.

The acylated first and/or second insulin polypeptide described hereincan be further modified to comprise a hydrophilic moiety. In somespecific embodiments the hydrophilic moiety can comprise a polyethyleneglycol (PEG) chain. The incorporation of a hydrophilic moiety can beaccomplished through any suitable means, such as any of the methodsdescribed herein. In some embodiments the acylated single chain analogcomprises an amino acid selected from the group consisting of a Cys,Lys, Orn, homo-Cys, or Ac-Phe, and the side chain of the amino acid iscovalently bonded to a hydrophilic moiety (e.g., PEG). In oneembodiment, the acyl group is attached to position A1, A14, A15, B1, B2,B10, or B22 (according to the amino acid numbering of the A and B chainsof native insulin), optionally via a spacer comprising Cys, Lys, Orn,homo-Cys, or Ac-Phe.

Alternatively, the acylated first and/or second insulin polypeptidecomprises a spacer, wherein the spacer is both acylated and modified tocomprise the hydrophilic moiety. Non-limiting examples of suitablespacers include a spacer comprising one or more amino acids selectedfrom the group consisting of Cys, Lys, Orn, homo-Cys, and Ac-Phe.

In some embodiments, the amino terminus of at least one N-terminal aminoacid of at least one of the A-chain polypeptides and the B-chainpolypeptides of the insulin receptor partial agonist is modified tocomprise a substituent. The substituent may be covalently linkeddirectly to the amino group of the N-terminal amino acid or indirectlyto the amino group via a spacer, wherein the spacer is positionedbetween the amino group of the N-terminal amino acid of the insulinpolypeptide and the substituent. The substituent may be an acyl moietyas discussed supra. The substituent may have the general formula RC(O)—,where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkyl chain,amino acid, peptide, polyethylene glycol (PEG), saccharides, which inparticular aspects RC(O)— may be acetyl, phenylacetyl, carbamoyl,N-alkyl carbamoyl, or alkoxycarbonyl. In particular aspects, thesubstituent is a carbamoyl group, acetyl group, glycine, methyl group,methoxy group, dimethyl group, isobutyl group, PEG1 group, or PEG2 group(see Examples herein for structures of the substituents). Carbamolyationof insulin has been disclosed by Oimoni et al., Nephron 46: 63-66 (1987)and insulin dimers comprising a carbamoyl groups at the N-terminus hasbeen disclosed in disclosed in published PCT Application No.WO2014052451 (E.g., MIU-90).

In particular embodiments, at least one N-terminal amino acid isconjugated via the N2 nitrogen to a substituent comprising anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides,which in particular aspects RC(O)— may be acetyl, phenylacetyl,carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. In particular aspects,the substituent is a carbamoyl group, acetyl group, glycine, methylgroup, methoxy group, dimethyl group, isobutyl group, PEG1 group, orPEG2 group.

In particular embodiments, the saccharide covalently linked to one ormore amino termini of the first and second insulin polypeptides may be amonosaccharide, see for example Dimer 51. In some embodiments, thesaccharide comprises one or more amine groups. In certain embodimentsthe saccharide and amine group are separated by a C₁-C₆ alkyl group,e.g., a C₁-C₃ alkyl group. In some embodiments, the saccharide isaminoethylglucose (AEG). In certain embodiments, a saccharide ligand isof the “D” configuration. In other embodiments, a saccharide ligand isof the “L” configuration. Below we show the structures of theseexemplary saccharides. Other exemplary saccharides will be recognized bythose skilled in the art.

In general, the saccharides may be directly or indirectly conjugated viaa linker to the amino terminus of one or more of the first and secondinsulin polypeptides. In particular aspects, the linker is analkyldioyl, —C(O)(CH₂)_(n)C(O)—, wherein n=0-45, 0-20, 0-10, or 0-5.

Exemplary substituents conjugated to the N-terminal amino group may be

wherein the wavy line indicates the bond between the substituent and theN-terminal amino group. The substituent may also be

wherein the wavy line indicates the bond between Me2 and the alphacarbon of the N-terminal amino acid.

Exemplary Insulin Dimers

In particular embodiments, the present invention provides insulin dimerswherein a first B29 or B28 Lys of a first insulin heterodimer moleculehaving a first A-chain polypeptide and first B-chain polypeptide and asecond B29 or B28 Lys of a second insulin heterodimer having a secondA-chain polypeptide and second B-chain polypeptide are conjugatedtogether by a bifunctional linker selected from the group consistingLinker 1, Linker 2, Linker 3, Linker 10, Linker 11, Liner 12, Linker 13,Linker 14, Linker 15, Linker 16, Linker 17, Linker 18, Linker 19, Linker20, Linker 21, Linker 22, Linker 23, Linker 24, Linker 25, Linker 26,Linker 27, Linker 28, Linker 29, Linker 30, Linker 31, Linker 32, Linker33, Linker 34, Linker 35, Linker 36, Linker 37, Linker 38, Linker 39,Linker 40, Linker 41, Linker 42, Linker 43, Linker 44, Linker 45, Linker46, Linker 47, Linker 48, Linker 49, and Linker 50 with the proviso thatwhen the bifunctional linker is Linker 10, Linker 11, Linker 12, Linker13, or Linker 14, at least one of the first or second A-chain or B-chainpolypeptides is conjugated at its N-terminal amino acid to a substituentas disclosed herein or at least the N-terminal amino acids of the firstinsulin heterodimer molecule are conjugated to a substituent asdisclosed herein or the N-terminal amino acids of both the first insulinheterodimer and second insulin heterodimer are conjugated to asubstituent. In particular embodiments, the substituent comprises anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides,which in particular aspects RC(O)— may be acetyl, phenylacetyl,carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. In particular aspects,the substituent is a carbamoyl group, acetyl group, glycine, methylgroup, methoxy group, dimethyl group, isobutyl group, PEG1 group, AEGgroup, AEG-C6 alkyl group, or PEG2 group.

In particular embodiments, the present invention provides insulin dimerswherein a first B29 or B28 Lys of a first insulin heterodimer moleculehaving a first A-chain polypeptide and first B-chain polypeptide isconjugated to a first linker selected from the group consisting ofLinker 5 and Linker 7 and a second B29 or B28 Lys of a second insulinheterodimer having a second A-chain polypeptide and second B-chainpolypeptide is conjugated to a second linker selected from the groupconsisting of Linker 4, Linker 6, Linker 8, and Linker 9 are conjugatedtogether via the first linker and the second linker. In particularembodiments, at least one of the first or second A-chain or B-chainpolypeptides is conjugated at its N-terminal amino acid to a substituentas disclosed herein or at least the N-terminal amino acids of the firstinsulin heterodimer molecule are conjugated to a substituent asdisclosed herein or the N-terminal amino acids of both the first insulinheterodimer and second insulin heterodimer are conjugated to asubstituent. In particular embodiments, the substituent comprises anN-hydroxysuccinimide ester linked to a group having the general formulaRC(O)—, where R can be R′CH₂, R′NH, R′O, and R′ can be H, linear alkylchain, amino acid, peptide, polyethylene glycol (PEG), saccharides,which in particular aspects RC(O)— may be acetyl, phenylacetyl,carbamoyl, N-alkyl carbamoyl, or alkoxycarbonyl. In particular aspects,the substituent is a carbamoyl group, acetyl group, glycine, methylgroup, methoxy group, dimethyl group, isobutyl group, PEG1 group, AEGgroup, AEG-C6 alkyl group, or PEG2 group.

In particular embodiments, the present invention provides insulin dimerswherein a first B29 or B28 Lys of a first insulin heterodimer moleculehaving a first A-chain polypeptide and first B-chain polypeptide isconjugated to a first linker selected from the group consisting ofLinker 5 and Linker 7 and a second B29 or B28 Lys of a second insulinheterodimer having a second A-chain polypeptide and second B-chainpolypeptide is conjugated to a second linker selected from the groupconsisting of Linker 5 and Linker 7, wherein the first and secondlinkers are conjugated together via a bridging linker having a structure

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG25. In particular embodiments, at least one of thefirst or second A-chain or B-chain polypeptides is conjugated at itsN-terminal amino acid to a substituent as disclosed herein or at leastthe N-terminal amino acids of the first insulin heterodimer molecule areconjugated to a substituent as disclosed herein or the N-terminal aminoacids of both the first insulin heterodimer and second insulinheterodimer are conjugated to a substituent. In particular embodiments,the substituent comprises an N-hydroxysuccinimide ester linked to agroup having the general formula RC(O)—, where R can be R′CH₂, R′NH,R′O, and R′ can be H, linear alkyl chain, amino acid, peptide,polyethylene glycol (PEG), saccharides, which in particular aspectsRC(O)— may be acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, oralkoxycarbonyl. In particular aspects, the substituent is a carbamoylgroup, acetyl group, glycine, methyl group, methoxy group, dimethylgroup, isobutyl group, PEG1 group, AEG group, AEG-C6 alkyl group, orPEG2 group.

In particular embodiments, the present invention provides insulin dimerswherein a first B29 or B28 Lys of a first insulin heterodimer moleculehaving a first A-chain polypeptide and first B-chain polypeptide isconjugated to a first linker selected from the group consisting ofLinker 4, Linker 6, Linker 8, and Linker 9 and a second B29 or B28 Lysof a second insulin heterodimer having a second A-chain polypeptide andsecond B-chain polypeptide is conjugated to a second linker selectedfrom the group consisting of Linker 4, Linker 6, Linker 8, and Linker 9,wherein the first and second linkers are conjugated together via abridging linker having a structure

N₃—R—N₃

wherein R is a covalent bond, a carbon atom, a phenyl, a heteroatom, oran optionally substituted group selected from the group consisting ofacyl, aliphatic, heteroaliphatic, aryl, heteroaryl, and heterocyclic. Inparticular aspects R is a C2, C3, C4, C6, C7, C8, C9 or C10 acyl groupor a PEG2, PEG3, PEG4, PEG5, PEG6, PEG7, PEG8, PEG9, PEG10, PEG11,PEG12, PEG13, or PEG 25. In particular embodiments, at least one of thefirst or second A-chain or B-chain polypeptides is conjugated at itsN-terminal amino acid to a substituent as disclosed herein or at leastthe N-terminal amino acids of the first insulin heterodimer molecule areconjugated to a substituent as disclosed herein or the N-terminal aminoacids of both the first insulin heterodimer and second insulinheterodimer are conjugated to a substituent. In particular embodiments,the substituent comprises an N-hydroxysuccinimide ester linked to agroup having the general formula RC(O)—, where R can be R′CH₂, R′NH,R′O, and R′ can be H, linear alkyl chain, amino acid, peptide,polyethylene glycol (PEG), saccharides, which in particular aspectsRC(O)— may be acetyl, phenylacetyl, carbamoyl, N-alkyl carbamoyl, oralkoxycarbonyl. In particular aspects, the substituent is a carbamoylgroup, acetyl group, glycine, methyl group, methoxy group, dimethylgroup, isobutyl group, PEG1 group, AEG group, AEG-C6 alkyl group, orPEG2 group.

In further embodiments the first and second insulin heterodimers maycomprise any of the insulin or insulin analog molecules disclosedherein.

The present invention also provides insulin dimers selected from

Wherein the disulfide linkages between the Cys₆ and Cys residues of theA-chain polypeptide and the disulfide linkages between the Cys₇ andCys₂₀ of the A-chain to the Cys₇ and Cys₁₉ of the B-chain polypeptide,respectively, are represented by the solid line therebetween; whereinthe linking moieties are covalently linked to the epsilon amino acid ofthe shown lysine residue, wherein the A-chain polypeptide for Dimers1-40, 42-52, 54-86, and 88-94 has the amino acid sequence shown in SEQID NO:1; the A-chain polypeptide for Dimer 56 has the amino acidsequence shown for SEQ ID NO:11; the B-chain polypeptide for Dimers1-17, 21-27, 36, 37, 39-40, and 42-52, 54-82, 84-86, and 88-94 has theamino acid sequence shown in SEQ ID NO:2; the B-chain polypeptide forDimers 18 and 32-35 has the amino acid sequence shown in SEQ ID NO:6;the B-chain polypeptide for Dimers 19 and 83 has the amino acid sequenceshown in SEQ ID NO:9; the B-chain polypeptide for Dimers 20, 28-31, and38 has the amino acid sequence shown in SEQ ID NO:10; and the A-chainpolypeptide and B-chain polypeptide for Dimers 53 and 87 are SEQ ID NO:7and SEQ ID NO:8, respectively.

Pharmaceutical Compositions

In accordance with one embodiment a pharmaceutical composition isprovided comprising any of the novel insulin dimers disclosed herein,preferably at a purity level of at least 90%, 91%, 92%, 93%, 94%, 95%,96%, 97%, 98% or 99%, and a pharmaceutically acceptable diluent, carrieror excipient. Such compositions may contain an insulin dimer asdisclosed herein at a concentration of at least 0.5 mg/ml, 1 mg/ml, 2mg/ml, 3 mg/ml, 4 mg/ml, 5 mg/ml, 6 mg/ml, 7 mg/ml, 8 mg/ml, 9 mg/ml, 10mg/ml, 11 mg/ml, 12 mg/ml, 13 mg/ml, 14 mg/ml, 15 mg/ml, 16 mg/ml, 17mg/ml, 18 mg/ml, 19 mg/ml, 20 mg/ml, 21 mg/ml, 22 mg/ml, 23 mg/ml, 24mg/ml, 25 mg/ml or higher. In one embodiment the pharmaceuticalcompositions comprise aqueous solutions that are sterilized andoptionally stored contained within various package containers. In otherembodiments the pharmaceutical compositions comprise a lyophilizedpowder. The pharmaceutical compositions can be further packaged as partof a kit that includes a disposable device for administering thecomposition to a patient. The containers or kits may be labeled forstorage at ambient room temperature or at refrigerated temperature.

The disclosed insulin dimers are believed to be suitable for any usethat has previously been described for insulin peptides. Accordingly,the insulin dimers disclosed herein can be used to treat hyperglycemia,or treat other metabolic diseases that result from high blood glucoselevels. Accordingly, the present invention encompasses pharmaceuticalcompositions comprising a insulin dimers as disclosed herein and apharmaceutically acceptable carrier for use in treating a patientsuffering from high blood glucose levels. In accordance with oneembodiment the patient to be treated using a insulin dimer disclosedherein is a domesticated animal, and in another embodiment the patientto be treated is a human.

One method of treating hyperglycemia in accordance with the presentdisclosure comprises the steps of administering the presently disclosedinsulin dimers to a patient using any standard route of administration,including parenterally, such as intravenously, intraperitoneally,subcutaneously or intramuscularly, intrathecally, transdermally,rectally, orally, nasally or by inhalation. In one embodiment thecomposition is administered subcutaneously or intramuscularly. In oneembodiment, the composition is administered parenterally and the insulinpolypeptide, or prodrug derivative thereof, is prepackaged in a syringe.

The insulin dimers disclosed herein may be administered alone or incombination with other anti-diabetic agents. Anti-diabetic agents knownin the art or under investigation include native insulin, nativeglucagon and functional analogs thereof, sulfonylureas, such astolbutamide (Orinase), acetohexamide (Dymelor), tolazamide (Tolinase),chlorpropamide (Diabinese), glipizide (Glucotrol), glyburide (Diabeta,Micronase, Glynase), glimepiride (Amaryl), or gliclazide (Diamicron);meglitinides, such as repaglinide (Prandin) or nateglinide (Starlix);biguanides such as metformin (Glucophage) or phenformin;thiazolidinediones such as rosiglitazone (Avandia), pioglitazone(Actos), or troglitazone (Rezulin), or other PPARy inhibitors; alphaglucosidase inhibitors that inhibit carbohydrate digestion, such asmiglitol (Glyset), acarbose (Precose/Glucobay); exenatide (Byetta) orpramlintide; Dipeptidyl peptidase-4 (DPP-4) inhibitors such asvildagliptin or sitagliptin; SGLT (sodium-dependent glucosetransporter 1) inhibitors; or FBPase (fructose 1,6-bisphosphatase)inhibitors.

Pharmaceutical compositions comprising the insulin dimers disclosedherein can be formulated and administered to patients using standardpharmaceutically acceptable carriers and routes of administration knownto those skilled in the art. Accordingly, the present disclosure alsoencompasses pharmaceutical compositions comprising one or more of theinsulin dimers disclosed herein, or a pharmaceutically acceptable saltthereof, in combination with a pharmaceutically acceptable carrier. Forexample, the pharmaceutical compositions comprising the insulin dimersdisclosed herein may optionally contain zinc ions, preservatives (e.g.,phenol, cresol, parabens), isotonicizing agents (e.g., mannitol,sorbitol, lactose, dextrose, trehalose, sodium chloride, glycerol),buffer substances, salts, acids and alkalis and also further excipients.These substances can in each case be present individually oralternatively as mixtures. Glycerol, dextrose, lactose, sorbitol andmannitol are customarily present in the pharmaceutical preparation in aconcentration of 100-250 mM, NaCl in a concentration of up to 150 mM.Buffer substances, such as, for example, phosphate, acetate, citrate,arginine, glycylglycine or TRIS (i.e.2-amino-2-hydroxymethyl-1,3-propanediol) buffer and corresponding salts,are present in a concentration of 5-250 mM, commonly from about 10-100mM. Further excipients can be, inter alia, salts or arginine.

In one embodiment the pharmaceutical composition comprises a lmg/mLconcentration of the insulin dimer at a pH of about 4.0 to about 7.0 ina phosphate buffer system. The pharmaceutical compositions may comprisethe insulin dimer as the sole pharmaceutically active component, or theinsulin dimer can be combined with one or more additional active agents.

All therapeutic methods, pharmaceutical compositions, kits and othersimilar embodiments described herein contemplate that insulin dimersinclude all pharmaceutically acceptable salts thereof.

In one embodiment the kit is provided with a device for administeringthe insulin dimers composition to a patient. The kit may further includea variety of containers, e.g., vials, tubes, bottles, and the like.Preferably, the kits will also include instructions for use. Inaccordance with one embodiment the device of the kit is an aerosoldispensing device, wherein the composition is prepackaged within theaerosol device. In another embodiment the kit comprises a syringe and aneedle, and in one embodiment the insulin dimer composition isprepackaged within the syringe.

The compounds of this invention may be prepared by standard syntheticmethods, recombinant DNA techniques, or any other methods of preparingpeptides and fusion proteins. Although certain non-natural amino acidscannot be expressed by standard recombinant DNA techniques, techniquesfor their preparation are known in the art. Compounds of this inventionthat encompass non-peptide portions may be synthesized by standardorganic chemistry reactions, in addition to standard peptide chemistryreactions when applicable.

The following examples are intended to promote a further understandingof the present invention.

EXAMPLES General Procedures

All chemicals were purchased from commercial sources, unless otherwisenoted. Reactions were usually carried out at ambient temperature or atroom temperature unless otherwise noted. Reactions sensitive to moistureor air were performed under nitrogen or argon using anhydrous solventsand reagents. The progress of reactions was monitored by analytical thinlayer chromatography (TLC), and ultra performance liquidchromatography-mass spectrometry (UPLC-MS). TLC was performed on E.Merck TLC plates precoated with silica gel 60F-254, layer thickness 0.25mm. The plates were visualized using 254 nm UV and/or by exposure tocerium ammonium molybdate (CAM) or p-anisaldehyde staining solutionsfollowed by charring. Ultra performance liquid chromatography (UPLC) wasperformed on a Waters Acquity™ UPLC® system.

UPLC-MS Method A: Waters Acquity™ UPLC® BEH C18 1.7 μm 1.0×50 mm columnwith gradient 10:90-95:5 v/v CH₃CN/H₂O+v 0.05% TFA over 2.0 min; flowrate 0.3 mL/min, UV wavelength 215 nm; UPLC-MS;

Method B: Waters Acquity™ UPLC® BEH C18 1.7 μm 2.1×100 mm column withgradient 60:40-100:0 v/v CH₃CN/H₂O+v 0.05% TFA over 4.0 min and100:0-95:5 v/v CH₃CN/H₂O+v 0.05% TFA over 40 sec; flow rate 0.3 mL/min,UV wavelength 200-300 nm; UPLC-MS;

Method C: Waters Acquity™ UPLC® BEH C18 1.7 μm 2.1×100 mm column withgradient 20:80-90:10 v/v CH₃CN/H₂O+v 0.05% TFA over 4.0 min and90:10-95:5 v/v CH₃CN/H₂O+v 0.05% TFA over 0.5 min; flow rate 0.3 mL/min,UV wavelength 200-300 nm; UPLC-MS;

Method D: Waters Acquity™ UPLC® BEH C8 1.7 μm 2.1×100 mm column withgradient 10:90-55:45 v/v CH₃CN/H₂O+v 0.05% TFA over 4.0 min and55:45-95:5 v/v CH₃CN/H₂O+v 0.05% TFA over 40 sec; flow rate 0.3 mL/min,UV wavelength 200-300 nm; UPLC-MS;

Method E: Waters Acquity™ UPLC® BEH300 C4 1.7 μm 2.1×100 mm column withgradient 10:90-50:50 v/v CH₃CN/H₂O+v 0.05% TFA over 4.3 min and50:50-70:30 v/v CH₃CN/H₂O+v 0.05% TFA over 0.5 min; flow rate 0.3mL/min, UV wavelength 200-300 nm; UPLC-MS;

Method F: Waters Acquity™ UPLC® BEH C8 1.7 μm 2.1×100 mm column withgradient 20:80-72.5:27.5 v/v CH₃CN/H₂O+v 0.05% TFA over 4.3 min and72.5:27.5-95:5 v/v CH₃CN/H₂O+v 0.05% TFA over 0.5 min; flow rate 0.3mL/min, UV wavelength 200-300 nm, and UPLC-MS;

Method G: Waters Acquity™ UPLC® BEH C8 1.7 μm 2.1×100 mm column withgradient 20:80-90:10 v/v CH₃CN/H₂O+v 0.1% TFA over 4.0 min and90:10-95:5 v/v CH₃CN/H₂O+v 0.1% TFA over 0.4 min; flow rate 0.3 mL/min,UV wavelength 200-300 nm.

Mass analysis was performed on a Waters SQ Detector with electrosprayionization in positive ion detection mode and the scan range of themass-to-charge ratio was 170-900 or a Waters Micromass® LCT Premier™ XEwith electrospray ionization in positive ion detection mode and the scanrange of the mass-to-charge ratio was 300-2000. The identification ofthe produced insulin conjugates or IRPA was confirmed by comparing thetheoretical molecular weight to the experimental value that was measuredusing UPLC-MS. For the determination of the linkage positions,specifically, insulin dimers were subjected to DTT treatment (for a/bchain) or Glu-C digestion (with or without reduction and alkylation),and then the resulting peptides were analyzed by LC-MS. Based on themeasured masses, the linkage positions were deduced.

Flash chromatography was performed using either a Biotage FlashChromatography apparatus (Dyax Corp.) or a CombiFlash® Rf instrument(Teledyne Isco). Normal-phase chromatography was carried out on silicagel (20-70 μm, 60 Å pore size) in pre-packed cartridges of the sizenoted. Ion exchange chromatography was carried out on a silica-basedmaterial with a bonded coating of a hydrophilic, anionicpoly(2-sulfoethyl aspartamide) (PolySULFOETHYL A column, PolyLC Inc.,250×21 mm, 5 μm, 1000 Å pore size). Reverse-phase chromatography wascarried out on C18-bonded silica gel (20-60 μm, 60-100 Å pore size) inpre-packed cartridges of the size noted. Preparative scale HPLC wasperformed on Gilson 333-334 binary system using Waters DELTA PAK C4 15μm, 300 Å, 50×250 mm column or KROMASIL® C8 10 μm, 100 Å, 50×250 mmcolumn, flow rate 85 mL/min, with gradient noted. Concentration ofsolutions was carried out on a rotary evaporator under reduced pressureor freeze-dried on a VirTis Freezemobile Freeze Dryer (SP Scientific).

Abbreviations: acetonitrile (AcCN), aqueous (aq),N,N-diisopropylethylamine or Hunig's base (DIPEA), N,N-dimethylformamide(DMF), dimethyl sulfoxide (DMSO), ethyl acetate (EtOAc),N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC),gram(s) (g), 1-hydroxybenzotriazole hydrate (HOBt), hour(s) (h or hr),mass spectrum (ms or MS), microgram(s) (μg), microliter(s) (μL),micromole (μmol), milligram(s) (mg), milliliter(s) (mL), millimole(mmol), minute(s) (min), retention time (R_(t)), room temperature (rt),saturated (sat. or sat′ d), saturated aq sodium chloride solution(brine), triethylamine (TEA), trifluoroacetic acid (TFA), andN,N,N′,N′-tetramethyl-O—(N-succinimidyl)uronium tetrafluoroborate(TSTU).

The term “RHI” refers to recombinant human insulin and is used toindicate that the insulin has the amino acid sequence characteristic ofnative, wild-type human insulin. As used herein in the tables, the termindicates that the amino acid sequence of the insulin comprising thedimer is that of native, wild-type human insulin.

Example 1

Synthesis of 2,5-dioxopyrrolidin-1-yl6-((6-((2,5-dioxopyrrolidin-1-yl)oxy)-6-oxohexyl)amino)-6-oxohexanoate(Linker 1; C6+NC6) is described.

Step 1 Benzyl 6-((6-(benzyloxy)-6-oxohexyl)amino)-6-oxohexanoate

To a mixture of adipic acid monobenzyl ester (600 mg, 2.54 mmol) and6-(benzyloxy)-6-oxohexan-1-aminium 4-methylbenzenesulfonate (1.0 g, 2.54mmol) in DMF (12.71 mL) was added HOBt (584 mg, 3.81 mmol), Hunig's base(888 μL, 5.08 mmol), and EDC (731 mg, 3.81 mmol). After stirringovernight, the reaction mixture was partitioned between sat. NaHCO₃ andEtOAc. The organic phase was separated, washed with 1.0 M HCl and brine,dried over Na₂SO₄, and concentrated to give the title compound as asemi-solid and used in the next step without further purification.UPLC-MS Method A: Rt=1.26 min, m/z=440.3 [M+1]

Step 2-6-((5-Carboxypentyl)amino)-6-oxohexanoic acid

A suspension of the product of Step 1 (1.08 g, 2.457 mmol) andPearlman's catalyst (20% wt on carbon, 173 mg, 0.246 mmol) in MeOH (50mL) was stirred under 50 psi H₂ overnight. The catalyst was filtered offand the filtrate was subjected to reverse-phase chromatography on C8phase (Kromasil, C8 10 μm 100 Å, 250×50 mm; solvent A=water/0.05% TFA,solvent B=AcCN/0.05% TFA), flow rate=85 mL/min, gradient B in A 5-30% in30 min. UPLC-MS Method A: Rt=0.40 min, m/z=260.15 [M+1].

Step 3 2,5-dioxopyrrolidin-1-yl6-((6-((2,5-dioxopyrrolidin-1-yl)oxy)-6-oxohexyl)amino)-6-oxohexanoate

To a solution of the product of Step 2 (50 mg, 0.193 mmol) in DMF (964μL) was added TSTU (116 mg, 0.386 mmol). After cooled down to 0° C., tothe mixture was added triethylamine (53.8 0.386 mmol). After stirringfor 45 minutes, formation of the desired compound was observed: UPLC-MSMethod A: Rt=0.71 min, m/z=453.4 [M+1]. The resulting2,5-dioxopyrrolidin-1-yl6-((6-((2,5-dioxopyrrolidin-1-yl)oxy)-6-oxohexyl)amino)-6-oxohexanoatewas used as 0.2 M solution in DMF without purification.

Example 2

Synthesis of bis(2,5-dioxopyrrolidin-1-yl)6,6′-(adipoylbis(azanediyl))dihexanoate (Linker 2; C6N+C6+NC6) isdescribed.

Step 1 dibenzyl 6,6′-(adipoylbis(azanediyl))dihexanoate

To a solution of 6-(benzyloxy)-6-oxohexan-1-aminium4-methylbenzenesulfonate (2.693 g, 6.84 mmol) and adipic acid (500 mg,3.42 mmol) in DMF (17.1 mL) was added Hunig's Base (1.793 mL, 10.26mmol), HOBt (1.572 g, 10.26 mmol), and EDC (1.968 g, 10.26 mmol). Afterstirring overnight, the reaction mixture was poured into water (500 mL)and stirred for 30 minutes. The title compound was collected throughfiltration as a solid and dried by air suction. UPLC-MS Method A:Rt=1.23 min, m/z=553.5 [M+1].

Step 2 Bis(2,5-dioxopyrrolidin-1-yl)6,6′-(adipoylbis(azanediyl))dihexanoate

The title compound was prepared using the procedure analogous to thosedescribed for EXAMPLE 1 substituting dibenzyl6,6′-(adipoylbis(azanediyl))dihexanoate for benzyl6-((6-(benzyloxy)-6-oxohexyl)amino)-6-oxohexanoate in Step 2. UPLC-MSMethod A: Rt=0.74 min, m/z=567.4 [M+1].

Example 3

Synthesis of(2S,2′S)-2,2′-(octanediylbis(azanediyl))bis(5-(2,5-dioxopyrrolidin-1-yl)oxy)-5-oxopentanoicacid) (Linker 3; gamma-Glu-suberic-gamma-Glu) is described.

Step 1(S)-5-(benzyloxy)-4-(8-(((S)-1-(benzyloxy)-4-carboxy-1-oxobutan-2-yl)amino)-8-oxooctanamide)-5-oxopentanoicacid

To a solution of H-GLU-OBZL (1.00 g, 4.21 mmol) in DMF (10.5 mL) wasadded triethylamine (5.875 mL, 42.1 mmol) followed by disuccinimidylsuberate (776 mg, 2.107 mmol). After stirring for 1 hour, the reactionmixture was concentrated and the resulting residue was purified on C18column (ISCO 44 g), flow=37 mL/min; gradient AcCN in water with 0.05%TFA: 2%-20% in 20 min followed by hold. After lyophilization, theintermediate bis-carboxylic acid was obtained. UPLC-MS Method B: Rt=2.66min, m/z=613.3 [M+1].

Step 2 Bis-N-hydroxysuccinimide ester of(S)-5-(benzyloxy)-4-(8-(((S)-1-(benzyloxy)-4-carboxy-1-oxobutan-2-yl)amino)-8-oxooctanamide)-5-oxopentanoicacid

To a suspension of the product of Step 1 (455 mg, 0.743 mmol) inacetonitrile (7.4 mL) was added TSTU (492 mg, 1.634 mmol) as a solidfollowed by triethylamine (228 μL, 1.634 mmol), at which point thesuspension dissolved. Stirred the reaction mixture for 1.5 hr andconcentrated on the rotovap at room temperature. The product waspurified by reverse-phase chromatography on C-8 phase (Column Kromasil,C8 10 μm 100 A, size 250×50 mm; solvent A=water/0.05% TFA, solventB=AcCN/0.05% TFA), Flow=85 mL/min, gradient B in A 10-80% in 30 min.After lyophilization of fractions, the bis-NHS ester was obtained.UPLC-MS Method B: Rt=2.77 min, m/z=807 [M+1].

Step 3.(2S,2′S)-2,2′-(octanediylbis(azanediyl))bis(5-((2,5-dioxopyrrolidin-1-yl)oxy)-5-oxopentanoicacid)

The product of Step 2 (250 mg, 0.310 mmol) was hydrogenated usingpalladium on carbon (66.0 mg, 0.031 mmol) as the catalyst, and acetonecontaining 0.1% TFA as the solvent (6.2 mL) at 1 atm of hydrogen,overnight. Catalyst was filtered off and the filtrate was concentratedto give the title compound. Pumped on high vacuum overnight. UPLC-MSMethod C: Rt=3.61 min, m/z=627.3 [M+1].

Example 4

General Method A: Synthesis of N^(6,B29) Insulin Conjugates (Analogs)

In an appropriate sized container, insulin or insulin analog wasdissolved, with gentle stirring, at room temperature in a mixed solvent:2:3 v/v 0.1 M Na₂CO₃:AcCN. After the mixture cleared, the pH wasadjusted to the value of 10.5-10.8 using alkaline solution, e.g., 0.1 NNaOH. In a separate vial, an activated ester intermediate (linkingmoiety) was dissolved in an organic solvent, e.g., DMSO, at roomtemperature. Aliquots of the solution of the activated ester (Linker)was added over a period of time to the solution containing insulin untilUPLC chromatogram showed that most of the unmodified insulin had beenreacted and that a substantial portion of the reaction mixture had beenconverted into B29-conjugated insulin. The reaction was quenched by theaddition of an amine nucleophile, e.g., 2-aminoethanol. The reactionsolution was stirred at room temperature for 30 minutes. The resultingsolution was carefully diluted with cold H₂O (20×) at 0° C. and its pHwas adjusted to a final pH of 2.5 using 1 N HCl (and 0.1 N NaOH ifneeded). The solution was first concentrated by ultrafiltration, eitherthrough a tangential flow filtration (TFF) system or using AmiconUltra-15 Centrifugal Units, with 1K, 3K or 10K MWCO membrane. Theconcentrated solution was usually first subjected to ion exchangechromatography (PolySULFOETHYL A column, PolyLC Inc., 250×21 mm, 5 μm,1000 Å; Buffer A: 0.1% (v/v) H₃PO₄/25% AcCN; Buffer B: 0.1% (v/v)H₃PO₄/25% AcCN/0.5 M NaCl). Fractions containing B29-conjugate withdesired purity were combined and concentrated using TFF system or AmiconUltra-15. The resulting solution was then further purified by reversephase HPLC (Waters C4 250×50 mm column, 10 μm, 1000 Å column or KromasilC8 250×50 mm, 10 μm, 100 Å column; Buffer A: 0.05-0.1% TFA in water;Buffer B: 0.05-0.1% TFA in AcCN). Fractions containing the titleconjugate were combined and freeze-dried or buffer exchanged using TFFsystem and/or Amicon Ultra-15 to give the title product.

Example 5

Synthesis of N^(6,29B)-5-azido-pentanoyl desB30 Insulin (A:Y19A)(Analog 1) is described.

In 20 mL scintillation vial, desB30 A:Y19A insulin (112 mg, 0.020 mmol)was dissolved, with gentle stirring, at room temperature in a mixedsolvent (2 mL, 2:3 v/v 0.1 M Na₂CO₃:AcCN). After the mixture cleared,the pH was adjusted to the value of 10.5-10.8 using alkaline solution,e.g., 0.1 N NaOH. In a separate 8 mL scintillation vial,2,5-dioxopyrrolidin-1-yl 5-azidopentanoate (Linker 5; see EXAMPLE 6)(4.79 mg, 0.020 mmol) was dissolved in DMSO (500 μL) at roomtemperature. Aliquots of the solution of the activated ester was addedover a period of time to the solution containing insulin until UPLCchromatogram showed that most of the unmodified insulin had been reactedand that a substantial portion of the reaction mixture had beenconverted into B29-conjugated insulin. The reaction was quenched by theaddition of an amine nucleophile, e.g., 2-aminoethanol. The reactionsolution was stirred at room temperature for 30 minutes. The resultingsolution was carefully diluted with cold H₂O (20×) at 0° C. and its pHwas adjusted to a final pH of 2.5 using 1.0 N HCl (and 0.1 N NaOH ifneeded). The solution was first concentrated by ultrafiltration usingAmicon Ultra-15 Centrifugal Units with 3K or 10K MWCO membrane. Theconcentrated solution was subjected to reverse phase HPLC (KROMASIL C8250×50 mm, 10 μm, 100 Å column, 25-35% Buffer B in Buffer A over 20 min;Buffer A: 0.05% TFA in water; Buffer B: 0.05% TFA in AcCN). Fractionscontaining Analog 1 were combined and then freeze-dried. UPLC-MS MethodD: Rt=3.91 min, m/z=1435.86 [(M+4)/4].

Example 6

The N^(6,29B)-acylated RHI Analog 2, Analog 3, and Analog 4 wereprepared for use in constructing dimers using “click” chemistry and wereprepared using General Method A or the procedure analogous to thosedescribed for EXAMPLE 4 but substituting recombinant human insulin andeither

-   (2,5-dioxopyrrolidin-1-yl pent-4-ynoate; Linker 4);

-   (2,5-dioxopyrrolidin-1-yl-azidopentanoate; Linker 5); or

(perfluorophenyl1-(bicyclo[6.1.0]non-4-yn-9-yl)-3-oxo-2,7,10,13,16-pentaoxa-4-azanonadecan-19-oate)(Linker 6) to make Analog 2, Analog 3, or Analog 4, respectively. Theanalogs were characterized using UPLC-MS Method D except for Analog 5,which was characterized using UPLC-MS Method F.

TABLE 1 Analog Linking moiety Rt (min) (M + 4)/4 2

4.08 1472.56 3

4.10 1483.89 4

3.94 1558.58 The wavy line indicates the bond between the epsilon aminogroup of the B29 Lys of the insulin molecule.

Example 7

Synthesis of N^(2,1A),N^(2,1B)-bis(carbamoyl) Human Insulin (Analog 5)is described.

To a suspension of RHI (1 g, 0.172 mmol) in water (50 mL) was added asolution of potassium phosphate, dibasic (0.249 g, 1.429 mmol) in water(5.0 mL). After stirring at room temperature for 30 minutes, to theresulting mixture was added potassium cyanate (0.279 g, 3.44 mmol). Thereaction mixture was allowed to stir for 16 hours. To stop the reaction,unreacted potassium cyanate was removed by TFF using MWCO 3Kdiafiltration device, and the product was isolated as a solid bylyophilization. The product contained about 10-35% ofA1/B1/B29-tris-urea-RHI, which optionally could be removed byreverse-phase chromatography on C8 phase (Column KROMASIL, C8 10 μm 100Å, 250×50 mm; solvent A=water/0.05% TFA, solvent B=AcCN/0.05% TFA), flowrate=85 mL/min, gradient B in A 26-34% over 30 min). UPLC-MS Method D:Rt=4.29 min, m/z=1474.6 (z=4). The N-terminal substituent has thestructure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid.

Example 8

Synthesis of N^(2,1A),N^(2,1B)-bis(carbamoyl) desB30 Human Insulin(Analog 6) is described.

The title compound was prepared using the procedure analogous to thosedescribed for EXAMPLE 7 substituting desB30 insulin for RHI. UPLC-MSMethod D: Rt=4.10 min, m/z=1448.9 (z=4). The N-terminal substituent hasthe structure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid.

Example 9

Synthesis of N^(2,1A),N^(2,1B)-bis(carbamoyl) Insulin lispro (Analog 7)is described.

The title compound was prepared using the procedure analogous to thosedescribed for EXAMPLE 7 substituting insulin lispro for RHI. UPLC-MSMethod D: Rt=4.07 min, m/z=1473.6 (z=4). The N-terminal substituent hasthe structure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid.

Example 10

Synthesis of N^(2,1A)-acetyl Human Insulin (Analog 8) is described.

To a solution of RHI (400 mg, 0.069 mmol) in DMSO (4.6 mL) was addeddropwise a solution of 2,5-dioxopyrrolidin-1-yl acetate

(10.82 mg, 0.069 mmol) in 100 μL of DMSO. After stirring for 3 hours,the reaction mixture was diluted with water (95 mL), acidified until pHof about 3, and then diafiltrated through Amicon Ultra-15 CentrifugalUnits with 3 or 10K MWCO membrane to remove most of DMSO. The resultingsolution was first subjected to ion exchange chromatography(PolySULFOETHYL A column, PolyLC Inc., 250×21 mm, 5 μm, 1000 Å, flowrate 15 mL/min; Buffer A: 0.1% (v/v) H₃PO₄/25% AcCN; Buffer B: 0.1%(v/v) H₃PO₄/25% AcCN/0.5M NaCl) using gradient 10-40% of Buffer B inBuffer A over 24 minutes. Fractions containing the desiredN^(2,1A)-acetyl-RHI was combined and concentrated, and then subjected toreverse phase chromatography on (KROMASIL, C8 10 μm 100 Å, 250×50 mm;solvent A=water/0.05% TFA, solvent B=AcCN/0.05% TFA, gradient 26-30% ofB in A). The modification position was confirmed using DTT analysis.UPLC-MS Method D: Rt=3.5 min and m/z=1463.5 (z=4). The N-terminalsubstituent has the structure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid.

Example 11

Synthesis of N^(2,1A),N^(2,1B)-bis(carbamoyl) N^(6,29B)-acylated RHI isdescribed.

Analog 5 conjugated to either 2,5-dioxopyrrolidin-1-yl-azidopentanoate(Linker 5) to construct Analog 9 or 2,5-dioxopyrrolidin-1-ylpent-4-ynoate (Linker 4) to construct Analog 10 were prepared usingGeneral Method A or the procedure analogous to those described forEXAMPLE 4.

Example 12

The following N^(6,29B)-acylated RHI analogs (Analog 11, Analog 12, andAnalog 13) were prepared for use in constructing dimers using “click”chemistry. The analogs were prepared using General Method A or theprocedure analogous to those described for EXAMPLE 4 but substitutingrecombinant human insulin (RHI) and the appropriate linking moietyselected from

to make Analog 11, Analog 12, or Analog 13, respectively. The analogswere characterized using UPLC-MS Method D except for Analog 12, whichwas characterized using UPLC-MS Method F.

TABLE 2 Analog Linking moiety Rt (min) (M + 4)/4 11

3.26 1488.11 12

3.97 1479.30 13

3.27 1502.26 The wavy line indicates the bond between the epsilon aminogroup of the B29 Lys of the insulin molecule.

Example 13

General Method B: Synthesis of N^(6,29B),N^(6,29B)′-Insulin Dimers UsingOrganic Base Condition

In an appropriate sized container, insulin or insulin analog issuspended at room temperature in an organic solvent or mixed aqueous(aq)/organic solvents, e.g., DMSO, in the presence of a base, e.g., TEA.The mixture is allowed to stir gently until insulin is completelydissolved. To the resulting solution is added an activated esterintermediate (linker) in solution of organic solvents, such as DMSO orDMF. After UPLC chromatogram shows that a substantial portion of thereaction mixture has converted into N^(6,29B),N^(6,B29B)′-insulin dimer(or N^(6,28B),N^(6,28B)′-insulin lispro dimer). The reaction mixture maybe subjected directly to reverse phase HPLC purification (Waters C4250×50 mm column, 10 μm, 1000 Å column or KROMASIL C8 250×50 mm, 10 μm,100 Å column; Buffer A: 0.05-0.1% TFA in deionized water; Buffer B:0.05-0.1% TFA in AcCN), or the reaction may be quenched by carefuldilution with cold acidic H₂O (20×, pH about 3.0) at 0° C. and its pH isadjusted to a final pH of 2.5 using 1 N HCl (and 0.1 N NaOH if needed).The solution may first be concentrated by ultrafiltration, eitherthrough a tangential flow filtration (TFF) system or using AmiconUltra-15 Centrifugal Units, with 1K, 3K or 10K MWCO membrane. Theconcentrated solution is usually first subjected to ion exchangechromatography (PolySULFOETHYL A column, PolyLC Inc., 250×21 mm, 5 μm,1000 Å; Buffer A: 0.1% (v/v) H3PO4/25% AcCN; Buffer B: 0.1% (v/v)H3PO4/25% AcCN/0.5 M NaCl). Fractions containing B29-conjugate withdesired purity are combined and concentrated using TFF system or AmiconUltra-15. The concentrated solution is then subjected to reverse phaseHPLC purification (Waters C4 250×50 mm column, 10 μm, 1000 Å column orKROMASIL C8 250×50 mm, 10 100 Å column; Buffer A: 0.05-0.1% TFA indeionized water; Buffer B: 0.05-0.1% TFA in AcCN). Fractions containingthe desired insulin dimer are combined and freeze-dried or bufferexchanged using TFF system and/or Amicon Ultra-15 to give theN^(6,29B),N^(6,29B)′-Insulin dimers.

Example 14

General Method C: Synthesis of N^(6,29B),N^(6,29B)′-Insulin Dimers UsingAqueous Base Conditions.

In an appropriate sized container, insulin or insulin analog isdissolved, with gentle stirring, at room temperature in a mixed solvent:2:3 v/v 0.1 M Na₂CO₃:AcCN. After the mixture cleared, the pH is adjustedto the value of 10.5-10.8 using alkaline solution, e.g., 0.1 N NaOH. Ina separate vial, an activated ester intermediate (linker) is dissolvedin an organic solvent, e.g., DMSO, at room temperature. Aliquots of thesolution of the activated ester is added over a period of time to thesolution containing insulin until UPLC chromatogram shows that most ofthe unmodified insulin has reacted and that a substantial portion of thereaction mixture has converted into N^(6,B29),N^(6,B29)′-insulin dimer(or N^(6,28B),N^(6,28B)-insulin lispro dimer). The reaction is quenchedby the addition of an amine nucleophile, e.g., 2-aminoethanol. Thereaction solution is stirred at rt for 30 minutes. The resultingsolution is carefully diluted with cold H₂O (20×) at 0° C. and its pH isadjusted to a final pH of 2.5 using 1 N HCl (and 0.1 N NaOH if needed).The solution is first concentrated by ultrafiltration, either through atangential flow filtration (TFF) system or using Amicon Ultra-15Centrifugal Units, with 1K, 3K or 10K MWCO membrane. The concentratedsolution is usually first subjected to ion exchange chromatography(PolySULFOETHYL A column, PolyLC Inc., 250×21 mm, 5 μm, 1000 Å; BufferA: 0.1% (v/v) H₃PO₄/25% AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5 MNaCl). Fractions containing B29-conjugate with desired purity arecombined and concentrated using TFF system or Amicon Ultra-15. Theresulting solution is then further purified by reverse phase HPLC(Waters C4 250×50 mm column, 10 μm, 1000 Å column or KROMASIL C8 250×50mm, 10 μm, 100 Å column; Buffer A: 0.05-0.1% TFA in water; Buffer B:0.05-0.1% TFA in AcCN). Fractions containing the title insulin dimer arecombined and freeze-dried or buffer exchanged using TFF system and/orAmicon Ultra-15 to give the N^(6,29B) N^(6,29B)′-Insulin dimers.

Example 15

This example illustrates the synthesis ofN^(6,B29)N^(6,B29)′-(2,2′-(ethane-1,2-diylbis(oxy))diacetyl)bis[insulinhuman] (Dimer 1).

Dissolved RHI (2.6 g, 0.448 mmol) in a mixture of Na₂CO₃ (0.1 M) (15.8mL) and AcCN (10.5 mL) and added 0.895 mL (0.179 mmol) of 0.2M DMFsolution of bis(2,5-dioxopyrrolidin-1-yl)2,2′-(ethane-1,2-diylbis(oxy))diacetate (Linker 8). Stirred the reactionmixture for 30 min and added additional portion of 0.895 mL (0.179 mmol)of 0.2M DMF solution of bis(2,5-dioxopyrrolidin-1-yl)2,2′-(ethane-1,2-diylbis(oxy))diacetate and stirred the reaction mixturefor 30 more min Poured the reaction mixture into 60 mL of 20% AcCN/0.1%TFA/water, adjusted pH to 2.5, and diafiltrated using Amicon Ultra-15with 10K MWCO membrane to concentrate until the resulting volume wasabout 10 mL. The resulting solution was subjected to ion-exchangechromatography (PolySULFOETHYL A column, 250×21 mm, 5 μm, 1000 Å,gradient 10-80% of Buffer B in Buffer A over 30 min; Buffer A: 0.1%(v/v) H₃PO₄/25% AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5M NaCl).Fractions containing the title compound was combined and concentrated.The resulting solution was then subjected to reverse phasechromatography (KROMASIL C8 250×50 mm, 10 μm, 100 Å column; gradient27-35% of AcCN with 0.05% TFA in water with 0.05% TFA). UPLC-MS MethodE: Rt=2.75 min, m/z=1960.4 (z=6), 1680.4 (z=7).

Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing the Linkingmoiety Insulin Rt or No. between the B29 and B29′ Lysine residues Ntermini (min) (M + 7)/7 1

RHI; A1, A1′, B1, B1′ = H 2.75 1960.4 The wavy line indicates the bondbetween the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Example 16

This example illustrates the synthesis ofN^(2,1A),N^(2,1A)′,N^(2,1B),N^(2,1B)′-Tetrakis(carbamoyl)-N^(6,B29),N^(6,B29)′-(hexanedioyl)bis[insulinhuman] (Dimer 2).

Dissolved N^(2,1A),N^(2,1B)-bis(carbamoyl) RHI (150 mg, 0.025 mmol) inDMSO (1 mL) and added triethylamine (0.106 mL, 0.764 mmol) followed bydropwise addition of di(N-succinimidyl) adipate (Linker 12) (4.33 mg,0.013 mmol) dissolved in 100 μL of DMSO. Stirred 1 hour and poured thereaction mixture into 20 mL of water. Acidified to pH=2 and diafiltratedusing 10K Amicon Ultra 15. The product was purified by ion-exchangechromatography using gradient 10-40% of Solvent B in Solvent A in 24minutes, and re-purified by reverse-phase chromatography on C-8 phasegradient B in A 26-36% in 30 minutes. UPLC-MS Method E: Rt=3.75 min,m/z=1983.9, (z=6).

Insulin Type; Dimer Structure of Dimer showing the Linking moietyInsulin Rt (M + 6)/6 or No. between the B29 and B29′ Lysine residues Ntermini (min) (M + 7)/7 2

RHI; A1, A1′, B1, B1′ = carbamoyl 3.75 1983.9 The wavy line indicatesthe bond between the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Examples 17

Table 3 shows dimers that were prepared using appropriate intermediates(linkers) following either General Method B or General Method C as notedusing the RHI, DesB30 RHI, insulin lispro, insulin aspart, insulinglargine, or the appropriate analog. For example, for dimers withcarbamoylated N-termini, Analog 5 or Analog 6 (DesB30) were used; fordimers with acetylated A1 N-termini, Analog 8 was used. The dimers werecharacterized using UPLC-MS Method D or UPLC-MS Method E, exhibitingeither six charged, i.e. [(M+6)/6], (or seven charged, i.e. [(M+7)/7])species of parent compound at certain retention time (Rt). The insulinand the insulin's molecules linked together by the linking moiety arethe same for each of the dimers shown in Table 3.

TABLE 3 Insulin Structure of Dimer showing the Linking Type; (M + 6)/6Dimer moiety between the B29 and B29′ Lysine Insulin Prep. Rt or No.residues N termini Method (min) (M + 7)/7 3

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.41 1988.745 4

RHI; A1, B1, A1′, B1′ = H C 3.76 1986.88 5

RHI; A1, B1, A1′, B1′ = H C 3.74 1972.6 6

RHI; A1, B1, A1′, B1′ = H C 3.80 1754.2 7

RHI; A1, B1, A1′, B1′ = H C 3.87 1728.8 8

RHI; A1, B1, A1′, B1′ = H C 3.70 1950.65 9

RHI; A1, B1, A1′, B1′ = H C 3.70 1954.9 10

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.97 1715.3 11

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.98 1727.9 12

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.73 1978.8 13

RHI; A1, A1′ = acetyl, B1, B1′ = H B 3.83 1973.8 14

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.10 1740.5 15

RHI; A1, B1, A1′, B1′ = H C 3.97 1716.0 16

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.80 1752.4 17

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.13 1778.7 18

Insulin lispro; A1, B1, A1′, B1′ = H C 3.74 1960.54 19

Insulin aspart; A1, B1, A1′, B1′ = H C 3.74 1966.13 20

RHI desB30; A1, B1, A1′, B1′ = H C 4.57 1926.04 21

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.48 1716.7 22

RHI; A1, B1, A1′, B1′ = H C 4.32 1974.06 23

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.38 1733.11 24

RHI; A1, B1, A1′, B1′ = carbamoyl B 3.59 1988.4 25

RHI; A1, B1, A1′, B1′ = H C 4.31 1708.35 26

RHI; A1, B1, A1′, B1′ = H C 4.08 1993.02 27

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.18 1732.48 28

RHI desB30; A1, B1, A1′, B1′ = carbamoyl B 3.86 1954.9 29

RHI desB30; A1, B1, A1′, B1′ = H C 3.75 1940.76 30

RHI desB30; A1, B1, A1′, B1′ = H C 3.77 1959.02 31

RHI desB30; A1, B1, A1′, B1′ = H C 4.00 1959.4 32

Insulin lispro; A1, B1, A1′, B1′ = carbamoyl B 3.81 1988.42 33

Insulin lispro; A1, B1, A1′, B1′ = H C 3.70 1974.04 34

Insulin lispro; A1, B1, A1′, B1′ = H C 3.80 1992.89 35

Insulin lispro; A1, B1, A1′, B1′ = H C 3.76 1992.86 36

RHI; A1, B1, A1′, B1′ = H C 4.29 1717.28 37

RHI; A1, B1, A1′, B1′ = carbamoyl B 4.01 1720.6 38

RHI desB30; A1, B1, A1′, B1′ = H C 3.88 1944.96 39

RHI; A1, B1, A1′, B1′ = H C 3.87 1978.88 88

RHI; A1, B1, A1′, B1′ = H D 3.39 1697.36 76

RHI; A1, B1, A1′, B1′ = H D 3.50 1709.73 83

Insulin aspart; A1, B1, A1′, B1′ = carbamoyl B 3.50 1994.39 85

RHI; A1, B1, A1′, B1′ = H D 3.46 1829.31 53

Insulin glargine; A1, B1, A1′, B1′ = H D 3.37 1788.87 87

Insulin glargine; A1, B1, A1′, B1′ = H D 3.43 1902.16 The wavy lineindicates the bond between the epsilon amino group of the B29 Lys andB29′ Lys, respectively.

Example 18

General Method D: Synthesis of N^(6,29B),N^(6,29B)′-Insulin Dimers UsingCu²⁺-Catalyzed Click Chemistry.

In an appropriate sized container, appropriate acetylene containinginsulin intermediate (Analog) was dissolved, with gentle stirring, atroom temperature in a mixed solvent of DMSO and aq. triethylammoniumacetate buffer (pH 7.0, final concentration 0.2 mM). In anotherappropriate sized container, appropriate azido containing insulinintermediate (Analog) was dissolved, with gentle stirring, at rt in amixed solvent of DMSO and water. Both solutions were combined,thoroughly mixed, degassed by gently bubbling N₂ through. To theresulting solution was added freshly prepared sodium ascorbate orascorbic acid solution (final concentration is 0.5 mM) and, afterthoroughly mixed, a solution of 10 mM CuSO₄ andtris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (i.e., TBTA ligand) in55% DMSO. After degassed by gently bubbling N₂ through and mixedthoroughly, the mixture was stored at rt, with occasional mixing,overnight. The reaction mixture was carefully diluted with a mix solvent(v/v 7:3 AcCN/water with 0.05% TFA) at 0° C. and pH was adjusted to 2.50using 0.1, 1.0 N HCl (and 0.1 N NaOH if needed). The solution was firstconcentrated by ultrafiltration, either through a tangential flowfiltration (TFF) system or using Amicon Ultra-15 Centrifugal Units, with1K, 3K, or 10K MWCO membrane. The concentrated solution was usuallyfirst subjected to ion exchange chromatography (PolySULFOETHYL A column,PolyLC Inc., 250×21 mm, 5 μm, 1000 Å; Buffer A: 0.1% (v/v) H₃PO₄/25%AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5 M NaCl). Fractionscontaining desired product with desired purity were combined andconcentrated using TFF system or Amicon Ultra-15. The resulting solutionwas then further purified by reverse phase HPLC (Waters C4 250×50 mmcolumn, 10 μm, 1000 Å column or KROMASIL C8 250×50 mm, 10 μm, 100 Åcolumn; Buffer A: 0.05-0.1% TFA in water; Buffer B: 0.05-0.1% TFA inAcCN). Fractions containing the desired product with desired purity werecombined and freeze-dried or buffer exchanged using TFF system and/orAmicon Ultra-15 to give the insulin dimers.

Table 4 lists Dimers 40, 41, 45, 46, 47, 59, 57, 79, 80, 82, and 84,which were prepared using the appropriate intermediates followingGeneral Method D. These dimers were characterized using UPLC-MS Method Dor UPLC-MS Method E or UPLC-MS Method G, exhibiting either six charged,i.e. [(M+6)/6], (or seven charged, i.e. [(M+7)/7]) species of parentcompound at certain retention time (Rt).

TABLE 4 Second First Insulin Structure of Dimer showing the Linking (M +6)/6 Dimer Insulin (′) moiety between the B29 and B29′ Rt or No.backbone backbone Lysine residues (min) (M + 7)/7 40 Analog 3 Analog 2

3.83 1970.38 41 Analog 1 Analog 2

3.88 1938.84 45 Analog 9 Analog 2

4.28 1985.30 46 Analog 3 Analog 10

4.50 1985.43 47 Analog 9 Analog 10

4.59 1714.34 75 Analog 3 Analog 2

3.40 1696.35 57 Analog 3 Analog 12

3.57 1975.90 79 Analog 11 Analog 13

3.38 1993.39 80 Analog 11 Analog 2

3.37 1973.83 82 Analog 11 Analog 12

3.34 1978.33 84 Analog 3 Analog 13

3.40 1990.54 The wavy line indicates the bond between the epsilon aminogroup of the B29 Lys and B29′ Lys, respectively.

Example 19

General Method E: Synthesis of N^(6,29)B^(, N6,29B)′-Insulin DimersUsing Cu²⁺-Catalyzed Double Click Chemistry.

In an appropriate sized container, appropriate azido containing insulinintermediate (Analog) was dissolved, with gentle stirring, at roomtemperature in a mixed solvent of DMSO and aq. triethylammonium acetatebuffer (pH 7.0, final concentration 0.2 mM). In another appropriatesized container, appropriate bis-acetylene containing bridging orintermediate linker was dissolved, with gentle stirring, at roomtemperature in a mixed solvent of DMSO and water. Both solutions werecombined, thoroughly mixed, degassed by gently bubbling N₂ through. Tothe resulting solution was added freshly prepared sodium ascorbate orascorbic acid solution (final concentration is 0.5 mM) and, afterthoroughly mixed, a solution of 10 mM CuSO₄ andtris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (i.e., TBTA ligand) in55% DMSO. After degassed by gently bubbling N₂ through and mixedthoroughly, the mixture was stored at room temperature, with occasionalmixing, overnight. The reaction mixture was carefully diluted with a mixsolvent (v/v 7:3 AcCN/water with 0.05% TFA) at 0° C. and pH was adjustedto 2.50 using 0.1, 1.0 N HCl (and 0.1 N NaOH if needed). The solutionwas first concentrated by ultrafiltration, either through a tangentialflow filtration (TFF) system or using Amicon Ultra-15 Centrifugal Units,with 1K, 3K, or 10K MWCO membrane. The concentrated solution was usuallyfirst subjected to ion exchange chromatography (PolySULFOETHYL A column,PolyLC Inc., 250×21 mm, 5 μm, 1000 Å; Buffer A: 0.1% (v/v) H₃PO₄/25%AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5 M NaCl). Fractionscontaining desired product with desired purity were combined andconcentrated using TFF system or Amicon Ultra-15. The resulting solutionwas then further purified by reverse phase HPLC (Waters C4 250×50 mmcolumn, 10 μm, 1000 Å column or KROMASIL C8 250×50 mm, 10 μm, 100 Åcolumn; Buffer A: 0.05-0.1% TFA in water; Buffer B: 0.05-0.1% TFA inAcCN). Fractions containing the desired product with desired purity werecombined and freeze-dried or buffer exchanged using TFF system and/orAmicon Ultra-15 to give the insulin dimers.

Table 5 lists Dimers 42-44 and 54 that were prepared using theappropriate intermediates following General Method E. The bis-acetylenebridging or intermediate linkers were

These dimers were characterized using UPLC-MS Method D or UPLC-MS MethodE, exhibiting either six charged, i.e. [(M+6)/6], (or seven charged,i.e. [(M+7)/7]) species of parent compound at certain retention time(Rt).

TABLE 5 Second First Insulin Structure of Dimer showing the Linking (M +6)/6 Dimer Insulin (′) moiety between the B29 and B29′ Rt or No.backbone backbone Lysine residues (min) (M + 7)/7 42 Analog 3 Analog 3

4.07 1501.00 43 Analog 3 Analog 3

4.47 1993.95 44 Analog 3 Analog 3

4.22 1494.14 59 Analog 3 Analog 3

3.78 1714.17 The wavy line indicates the bond between the epsilon aminogroup of the B29 Lys and B29′ Lys, respectively.

Example 20

This example illustrates the synthesis ofN^(2,1A),N^(2,1A)′,N^(2,1B),N^(2,1B)′-Tetrakis(acetyl or PEG1 or methoxyacetyl)-Dimers (Dimer 48, 55, 56, 69, and 70).

To a solution of Dimer 40, 19, or 4 (21 mg, 1.777 μmol) in DMSO (2 mL)at room temperature was added TEA (3.96 μL, 0.028 mmol) and then asolution of 2,5-dioxopyrrolidin-1-yl acetate (2.23 mg, 0.014 mmol) inDMSO (100 μL) or other appropriate N-hydroxysuccinimide activated ester(2,5-dioxopyrrolidin-1-yl methoxy acetate or 2,5-dioxopyrrolidin-1-ylPEG1 acetate) in DMSO (100 μL). After 3 hours, the reaction mixture wasdiluted with 12 mL of mixture of water/AcCN=7/3 with 0.1% TFA, and pHwas adjusted until 2.5. The resulting clear solution was concentrated byAmicon Ultra 15 Centrifuge Filters with 10K MWCO membrane. The resultingsolution was first subjected to ion exchange chromatography(PolySULFOETHYL Å, 250×21 mm, 5 μm, 1000 Å, 15 mL/min, gradient from 5%to 45% in 30 min; Buffer A: 0.1% (v/v) H₃PO₄/25% Acetonitrile in water;Buffer B: 0.1% (v/v) H₃PO₄/25% Acetonitrile/0.5 M NaCl in water).Fractions containing desired product with desired purity were combinedand concentrated using Amicon Ultra-15 with 10K MWCO membrane. Theresulting solution was then subjected to reverse phase HPLC (KROMASIL C8250×50 mm, 10 μm, 100 Å column; Buffer A: 0.05% TFA in AcCN/H₂O; BufferB: 0.05% AcCN; flow rate 85 mL/min). The desired fractions were combinedand freeze-dried to give Dimer 48, 55, 56, 69, or 70 as shown in Table6. UPLC-MS Method F or G was used.

The N-terminal substituents have the structure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid.

TABLE 6 Structure of Dimer showing the Linking Insulin Type; (M + 6)/6Dimer moiety between the B29 and B29′ Lysine Insulin Rt or No. residuesN termini (min) (M + 7)/7 48

RHI; A1, B1, A1′, B′ = acetyl 4.71 1998.93 55

RHI; A1, B1, A′, B′ = acetyl 3.61 1987.97 56

RHI; A1, B1, A1′, B′ = PEG1 3.53 1729.22 69

RHI; A1, B1, A1′, B′ = acetyl 3.55 1727.31 70

RHI; A1, B1, A1′, B′ = methoxy acetyl 3.67 1744.71 The wavy lineindicates the bond between the epsilon amino group of the B29 Lys andB29′ Lys, respectively.

Example 21

Table 7 shows Dimers 49, 50, and 51 and shows the acyl groups linked tothe amino groups of N^(2,A1),N^(2,B1),N^(2,A1)′ and N^(2,B1)′. Thesedimers were prepared from Dimer 40 using the procedures analogous tothat described for making Dimer 48 but substituting the appropriateN-hydroxysuccinimide activated esters for 2,5-dioxopyrrolidin-1-ylacetate to produce Dimers 49, 50, and 51. The activated esters were2,5-dioxopyrrolidin-1-yl Fmoc-glycine acetate

2,5-dioxopyrrolidin-1-yl PEG2 acetate

and 2,5-dioxopyrrolidin-1-yl AEG-C6 acetate, wherein AEG isaminoethylglucose

These dimers were characterized using either UPLC-MS Method F (Dimers 50and 51) or UPLC-MS Method G (Dimer 49), exhibiting either six charged,i.e. [(M+6)/6], (or seven charged, i.e. [(M+7)/7]) species of parentcompound at certain retention time (Rt). The dimers are shown in Table7.

The N-terminal substituents have the structure

TABLE 7 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 49

RHI; A1, A1′, B1, B1′ = glycine 3.62 1722.06 50

RHI; A1, A1′, B1, B1′ = PEG2 4.85 1764.16 51

RHI; A1, A1′, B1, B1′ = AEM-C6 4.06 1880.19 The wavy line indicates thebond between the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Example 22

This example illustrates the synthesis of Dimer 52 using copper-freeclick chemistry.

To a solution of Analog 3 (10 mg, 1.686 μmol) in 1.0 mL of 3:2 v/vH₂O/AcCN at room temperature was added a solution of Analog 4 (10.5 mg,1.686 μmol) in 1.0 mL of 3:2 v/v H₂O/AcCN. After stirring at roomtemperature for 2 hours, the reaction mixture was first subjected to ionexchange chromatography (PolySULFOETHYL Å, 250×21 mm, 5 μm, 1000 Å, 15mL/min, gradient from 5% to 45% in 30 min; Buffer A: 0.1% (v/v)H₃PO₄/25% Acetonitrile in water; Buffer B: 0.1% (v/v) H₃PO₄/25%Acetonitrile/0.5 M NaCl in water). Fractions containing desired productwith desired purity were combined and concentrated using Amicon Ultra-15with 3K or 10K MWCO membrane. The resulting solution was then subjectedto reverse phase HPLC (KROMASIL C8 250×50 mm, 10 μm, 100 Å column;Buffer A: 0.05% TFA in AcCN/H₂O; Buffer B: 0.05% AcCN; flow rate 85mL/min). The desired fractions were combined and freeze-dried to giveDimer 52. UPLC-MS Method F: Rt=3.73 min, m/z=1738.59 [(M+7)/7+1]. Theresults are shown in Table 8.

TABLE 8 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 52

RHI; A1, A1′ = H, B1, B1′ = carbamoyl 3.73 1738.59 The wavy lineindicates the bond between the epsilon amino group of the B29 Lys andB29′ Lys, respectively.

Example 23

This example illustrates the synthesis ofN^(2,1A),N^(2,1A)′,N^(2,1B),N^(2,1B)′-Tetrakis(dimethyl orisobutyl)-Dimers (Dimers 60, 58, 65, and 67).

Dimer 40, 19, or 4 (100 mg, 8.46 μmol) was dissolved (suspension) inWater (10 ml) and adjusted to pH=4.0 by acetic acid solution, thenformaldehyde (0.013 ml, 0.169 mmol) or isobutyraldehyde (0.025 ml, 0.272mmol) was added, followed by addition of a freshly prepared solution ofsodium cyanoborohydride (10.63 mg, 0.169 mmol) in Water (500 μL). Theprecipitate was formed. The mixture is gently stirred. After completionof the reaction about 1 hour, the mixture is carefully acidified bydropwise addition of 1N HCl to pH 2.9. The suspension became clearsolution. The mixture were purification by reverse phase prep HPLC (C-8column, 50×250 cm, 85 ml/min, gradient from 29% to 36% in 25 min).(Water with 0.1% TFA and MeCN with 0.05% TFA). The desired fractionswere lyophilyzed to give the dimers (19.9 mg, 1.506 μmol, 17.80% yield).UPLC-MS Method D: Rt=3.31 min, m/z=1989.44 [(M+6)/6+1].

The N-terminal substituents have the structure

wherein the wavy line indicates the bond between the substituent and theN2 nitrogen of the N-terminal amino acid, or

wherein the wavy line indicates the bond between the N2 nitrogen and theC2 carbon of the N-terminal amino acid.

The dimers are shown in Table 9.

TABLE 9 Insulin Structure of Dimer showing the Linking Type; (M + 6)/6Dimer moiety between the B29 and B29′ Lysine Insulin Rt or No. residuesN termini (min) (M + 7)/7 60

RHI; A1, B1, A1′, B′ = Me2 3.31 1989.44 58

RHI; A1, B1, A1′, B′ = Me2 3.42 1978.48 65

RHI; A1, B1, A1′, B′ = isobutyl 4.13 1997.04 67

RHI; A1, B1, A1′, B′ = Me2 3.42 1719.39 The wavy line indicates the bondbetween the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Example 24

Synthesis of Dimers 61, 62, 63, 64, and 66 was as follows.

The synthesis of 2,5-dioxopyrrolidin-1-yl6-((2-((2,5-dioxopyrrolidin-1-yl)oxy)-2-oxoethyl)amino)-6-oxohexanoate(C6-glycine linker; Linker 24) is described.

Step 1 Benzyl(2,5-dioxopyrrolidin-1-yl) adipate

To a solution of 6-(benzyloxy)-6-oxohexanoic acid (5 g, 21.16 mmol) inDMF (10 mL) at 0° C. was added N-ethyl-N-isopropylpropan-2-amine (4.44mL, 25.4 mmol) followed by TSTU (7.01 g, 23.28 mmol). The reaction wasstirred at 0° C. for 1 hour and room temperature for 1 hour. The mixturewas poured to ice-water/ethyl ether mixture (1/1, 100 mL). The mixturewas extracted with ethyl ether (3×50 mL), washed with water (2×10 mL)and brine (10 mL). The organic layer was dried over MgSO₄, filteredthrough a pad of celite and concentrate to give the titled compound ascolorless syrup (5.2 g, 15.6 mmol, 74%). LC-MS 2 min: Rt=1.05 min,m/z=334.1 [M+1].

Step 2-((Carboxymethyl)amino)-6-oxohexanoic acid

To a solution of glycine (225 mg, 3.0 mmol) in DMF (2.5 mL) was addedthe product of Step 1 (1.0 g, 3.0 mmol) in DMF (2.5 mL) drop wisefollowed by TEA (418 3.0 mmol). The reaction was stirred at roomtemperature for 18 hr. DMF was removed by under reduced pressure. Thecrude was purified by C18 reverse phase chromatography (eluted with0-40% AcCN/water in 16 column volumes (CV)). Fractions containingdesired product were combined, concentrated and lyophilized to giveintermediate (6-(benzyloxy)-6-oxohexanoyl) glycine. To aboveintermediate in water (3 mL), was added Pd/C (10%, 160 mg, 0.15 mmol).The reaction was stirred at room temperature under hydrogen balloon for18 hr. The mixture was filtered through a pad of celite, washed withMeOH/water (1/1, 10 ml). The filtrate was concentrated and lyophilizedto give the titled compound (400 mg, 2.2 mmol, 66%). LC-MS 2 min:Rt=0.28 min, m/z=204.03 [M+1].

Step 3. 2,5-dioxopyrrolidin-1-yl6-((2-((2,5-dioxopyrrolidin-1-yl)oxy)-2-oxoethyl)amino)-6-oxohexanoate

To the product of Step 2 (10 mg, 0.049 mmol) in DMF (0.5 mL) at 0° C.was added TEA (0.015 mL, 0.108 mmol) followed by TSTU (31.1 mg, 0.103mmol). The reaction was warmed to room temperature and stirred at thattemperature for 1 hr. TLC (EtOAc/MeOH/Water/AcCN: 2:1:1:1 (v:v:v:v))showed formation of desired product (Rf: 0.25) and no starting materialleft. The crude material was used for constructing dimers withoutpurification.

Linker 25 (C6-alanine), Linker 26 (C6-isoleucine), Linker 27(C6-leucine), and Linker 28 (C6-valine) wherein the amino acidcomprising the C6-amino acid linker is alanine, isoleucine, leucine, andvaline, respectively, were synthesized similar to the process shownabove. Dimers were constructed using the above linkers using prep.Method D. The results are shown in Table 10.

TABLE 10 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 61

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.90 1993.24 62

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.91 1995.62 63

RHI; A1, B1, A1′, B1′ = Carbamoyl 4.02 1714.70 64

RHI; A1,B1,A1′, B1′ = Carbamoyl 3.80 1716.61 66

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.73 1716.93 The wavy line indicatesthe bond between the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Example 25

Synthesis of Dimers 73, 89, 90, 91, 92, and 93 was as follows.

The synthesis of bis 2,5-dioxopyrrolidin-1-yl3,3′-(1,3-phenylene)dipropionate (dipropyl phenyl; Linker 29) isdescribed.

Step 1. bis 2,5-dioxopyrrolidin-1-yl 3,3′-(1,3-phenylene)dipropionate

To a solution of 3,3′-(1,3-phenylene)dipropionoic acid (21.8 mg, 0.098mmol) in DMF (0.6 mL) at 0° C. was added TEA (29 mL, 0.206 mmol)followed by TSTU (62.0 mg, 0.206 mmol). The reaction was warmed to roomtemperature and stirred at that temperature for 1 hour. TLC(EtOAc/MeOH/Water/AcCN: 2/1/1/1) showed formation of desired product(Rf: 0.25) and no starting material left. UPLC-MS Method B: Rt=3.47 min,m/z=417.19 [M+1]. The product was used without further purification toconstruct Dimer 73 using Analog 5 using Method D.

The synthesis of bis(2,5-dioxopyrrolidin-1-yl) benzene-1,3-dicarboxylate(terephthalate; Linker 34) is described.

Step 1. bis(2,5-dioxopyrrolidin-1-yl) benzene-1, 3-dicarboxylate

At 0° C., to a solution of terephthalic acid (100 mg, 0.602 mmol) in THF(2 ml) was added2-(2,5-dioxopyrrolidin-1-yl)-1,1,3,3-tetramethylisouroniumtetrafluoroborate (371 mg, 1.234 mmol) followed byN-ethyl-N-isopropylpropan-2-amine (0.222 ml, 1.234 mmol)). After 30minutes, the ice bath was removed. The solution was stirred at roomtemperature for 1 hour. An additional 25 mL THF was added and thereaction was left overnight at room temperature. Product wasconcentrated down to about 5 mL and a portion was used as is withoutfurther purification to construct Dimer 89 using RHI using Method D.Remaining material was diluted with ethylacetate (200 mL) and washedwith brine (10 mL), organic layer was dried with Na2SO4, filtered andconcentrated.

Synthesis of bis (2,5-dioxopyrrolidin-1-yl) isophthalate (isophthalate;Linker 35) is described.

Step 1. bis (2,5-dioxopyrrolidin-1-yl) isophthalate

To isophthalic acid (54 mg, 0.325 mmol) in DMSO (1 mL) was added TSTU(215 mg, 0.715 mmol) followed by TEA (0.137 mL, 0.975 mmol). LC-MS 2min: Rt=0.79 min, m/z=721.28 [2M+1]. The product was used withoutpurification to construct Dimer 90 using Analog 5 and Dimer 91 using RHIin Method E.

Synthesis of bis (2,5-dioxopyrrolidin-1-yl)4-((tert-butoxycarbonyl)amino) heptanedioate (heptanedioate; Linker 36)is described.

Step 1. bis (2,5-dioxopyrrolidin-1-yl) 4-((tert-butoxycarbonyl)amino)heptanedioate

To 4-((tert-butoxycarbonyl)amino)heptanedioic acid (16.5 mg, 0.06 mmol)in DMSO (0.5 mL) was added TSTU (39.7 mg, 0.132 mmol) followed by TEA(0.025 mL, 0.180 mmol). LC-MS 2 min: Rt=0.90 min, m/z=470.34 [M+1]. Theproduct was used without purification to construct Dimer 92 using Analog5 and Dimer 93 using RHI in Method E.

The results are shown in Table 11.

TABLE 11 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 73

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.55 1711.57 89

RHI; A1, B1, A1′, B1′ = H 3.43 1678.64 90

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.67 1703.20 91

RHI; A1, B1, A1′, B1′ = H 3.52 1678.69 92

RHI; A1, B1, A1′, B1′ = Carbamoyl 3.56 1704.64 93

RHI; A1, B1, A1′, B1′ = H 3.33 1680.18 The wavy line indicates the bondbetween the epsilon amino group of the B29 Lys and B29′ Lys,respectively.

Example 26

The synthesis of Dimers 71, 72, 77, 78, 81, and 87 was as follows.Synthesis of bis(2,5-dioxopyrrolidin-1-yl)(1S,4S)-cyclohexane-1,4-dicarboxylate (Linker 30; trans-cyclohexane1,4-diacid) is described.

To a solution of (1S,4S)-cyclohexane-1,4-dicarboxylic acid (200 mg,1.162 mmol) in DCM (11 mL) at 0° C. was added TSTU (734 mg, 2.439 mmol)and DIPEA (0.5 mL, 2.86 mmol). The resulting reaction mixture wasstirred at room temperature for 1 hour. The product was crushed out inreaction solution as white solid; filtered and washed with DCM (2×5 ml);and dried in vacuo to obtain the title compound. UPLC-MS calculated forC₁₆H₁₈N₂O₈, 366.11, observed m\e: 367.16 (M+H)+, (Rt: 3.20/5.00minutes). UPLC-MS Method A. ¹H NMR (500 MHz, DMSO): δ 2.81-2.89 (m; 2H);2.80 (s; 8H); 2.02-2.10 (m; 4H); 1.57-1.63 (m; 4H).

Synthesis of bis(2,5-dioxopyrrolidin-1-yl)(1R,4R)-cyclohexane-1,4-dicarboxylate (Linker 31; cis-cyclohexane1,4-diacid) is described.

To a solution of (1R,4R)-cyclohexane-1,4-dicarboxylic acid (200 mg,1.162 mmol) in DCM (11 mL) at 0° C. was added TSTU (734 mg, 2.439 mmol)and DIPEA (0.5 mL, 2.86 mmol). The resulting reaction mixture wasstirred at room temperature for 1 hour. The residue was purified bysilica gel chromatography (0-100% EtOAc/Hexanes) to provide the titlecompound. UPLC-MS calculated for C₁₆H₁₈N₂O₈, 366.11, observed m/z:367.17 (M+H)+, (Rt: 3.17/5.00 minutes). UPLC-MS Method A. ¹H NMR (500MHz, DMSO): δ 3.02-3.08 (m; 2H); 2.80 (s; 8H); 1.80-1.90 (m; 8H).

Synthesis of 1-(tert-butyl) 3,5-bis(2,5-dioxopyrrolidin-1-yl)(3R,5S)-piperidine-1,3,5-tricarboxylate (Linker 32) is described.

To a solution of(3R,5S)-1-(tert-butoxycarbonyl)piperidine-3,5-dicarboxylic acid (200 mg,0.734 mmol) in DMF (7 mL) at 0° C. was added TSTU (485 mg, 1.611 mmol)and DIPEA (0.3 mL, 1.718 mmol). The resulting reaction mixture wasstirred at room temperature for 2 hour. The residue was purified bysilica chromatography (0-100% EtOAc/Hexanes) to provide the titlecompound. UPLC-MS calculated for C₂₀H₂₅N₃O₁₀, 467.15, observed m\e:468.30 (M+H)+, (Rt: 0.98/2.00 minutes). UPLC-MS Method A.

General Method F: Synthesis of N^(6,29)B,N^(6,29)B′-Insulin Dimers UsingOrganic Base Condition

In an appropriate sized container, insulin or insulin analog issuspended at room temperature in an organic solvent or mixed aq/organicsolvents, e.g., DMSO, in the presence of a base, e.g., TEA, or1,1,3,3-tetramethylguanidine (TMG). The mixture is allowed to stirgently until insulin is completely dissolved. To the resulting solutionis added an activated ester intermediate in solution of organicsolvents, such as DMSO or DMF. After UPLC, chromatogram shows that asubstantial portion of the reaction mixture has converted intoN^(6,29)B, N^(6,B29B)′-insulin dimer (or N^(6,28B),N^(6,28B)′-insulinlispro dimer), the reaction solution was transfered, via autopipette, toa 50 mL centrifuge tube containing IPAc/MTBE (v/v 4:1) (45 mL). Theaddition was made dropwise. The resulting white suspension wascentrifuged (3000 rpm, 15 minutes, at 4 C) to generate a clearsupernatant and a white pellet. The supernatant was drawn off and whitepellet was dried in vacuo. The white pellet containing crudeintermediate was then dissolved in 2 mL of TFA at 0 C and stirred for 10minutes at same temperature. Upon completion of the de-boc reaction, thereaction solution was transferred, via autopipette, to a 50 mLcentrifuge tube containing MTBE (45 mL). The addition was made dropwise.The resulting white suspension was centrifuged (3000 rpm, 15 minutes, at4° C.) to generate a clear supernatant and a white pellet. Thesupernatant was drawn off and white pellet was dried in vacuo. andre-dissolved in CH₃CN/H₂O (v/v 1:4) solution. Reaction mixture may besubjected directly to reverse phase HPLC purification (Waters C4 250×50mm column, 10 μm, 1000 Å column or KROMASIL C8 250×50 mm, 10 μm, 100 Åcolumn; Buffer A: 0.05-0.1% TFA in deionized water; Buffer B: 0.05-0.1%TFA in AcCN), or the reaction may be quenched by careful dilution withcold acidic H₂O (20×, pH˜3.0) at 0° C. and its pH is adjusted to a finalpH of 2.5 using 1 N HCl (and 0.1 N NaOH if needed). The solution mayfirst be concentrated by ultrafiltration, either through a tangentialflow filtration (TFF) system or using Amicon Ultra-15 Centrifugal Units,with 1K, 3K or 10K MWCO membrane. The concentrated solution is usuallyfirst subjected to ion exchange chromatography (PolySULFOETHYL A column,PolyLC Inc., 250×21 mm, 5 μm, 1000 Å; Buffer A: 0.1% (v/v) H₃PO₄/25%AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5 M NaCl). Fractionscontaining B29-conjugate with desired purity are combined andconcentrated using TFF system or Amicon Ultra-15. The concentratedsolution is then subjected to reverse phase HPLC purification (Waters C4250×50 mm column, 10 μm, 1000 Å column or KROMASIL C8 250×50 mm, 10 μm,100 Å column; Buffer A: 0.05-0.1% TFA in deionized water; Buffer B:0.05-0.1% TFA in AcCN). Fractions containing the desired insulin dimerare combined and freeze-dried or buffer exchanged using TFF systemand/or Amicon Ultra-15 to give the N^(6,29B),N^(6,29B)′-Insulin dimers.

Table 12 lists Dimers 71, 72, 77, 78, 81, and 87, which were preparedusing the appropriate linker following either General Method B (Dimers77 and 78), General Method C (Dimers 71 and 72) or General Method F(Dimers 81 and 87). These dimers were characterized using UPLC-MS MethodD or UPLC-MS Method E, exhibiting either six charged, i.e. [(M+6)/6],(or seven charged, i.e. [(M+7)/7]) species of parent compound at certainretention time (Rt).

TABLE 12 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 71

RHI; A1, B1, A1′, B1′ = H 3.05 1959.33 1679.86 72

RHI; A1, B1, A1′, B1′ = H 3.07 1959.33 1679.86 81

RHI; A1, B1, A1′, B1′ = H 3.37 1959.48 1679.74 77

RHI; A1, B1, A1′, B1′ = carbamoyl 3.50 1988.07 1704.29 78

RHI; A1, B1, A1′, B1′ = carbamoyl 3.52 1988.08 1704.35 86

RHI: A1, B1, A1′, B1′ = carbamoyl 3.48 1988.18 1704.24 The wavy lineindicates the bond between the epsilon amino group of the B29 Lys andB29′ Lys, respectively.

Example 26

Synthesis of Dimer 68 and Dimer 74 was as follows.

Synthesis of bis(2,5-dioxopyrrolidin-1-yl)6,6′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))dihexanoate(Linker 33; C6N-chloro-1,3,5-Triazine-NC6) is described.

The solution of 2,4,6-trichloro-1,3,5-triazine (80 mg, 0.434 mmol) andmethyl 6-aminohexanoate (129 mg, 0.889 mmol) HCl salt in CH₂Cl₂ (1 mL)was cooled to −30° C. A solution of DIPEA (0.379 mL, 2.169 mmol) inCH₂Cl₂ (1 mL) was added dropwise. The mixture was stirred at −30°C.-room temperature for 5 hours. Then added CH₂Cl₂ (20 mL) and washedwith aqueous HCl (1 M) (2×10 mL), aqueous NaHCO₃ (10 ml) and brine (10mL). The organic layer dried over sodium sulfate and filtered,concentrated by vacuum to furnish dimethyl6,6′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))dihexanoate (135mg, 0.336 mmol).

To the solution of dimethyl6,6′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))dihexanoate (135mg, 0.336 mmol) in THF (0.5 ml) and methanol (0.5 mL) was added aqueous(2M) LiOH (504 1.008 mmol). The mixture was stirred at room temperaturefor 1 hour and then concentrated in vacuo to produce a dried residue.Dissolved the residue in water and neutralized with aq HCl. Collectedthe precipitate by filtration and washed it with water. Dried the solidin vacuo to furnish of6,6′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))dihexanoic acid.

To a solution of6,6′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))dihexanoic acid(108 mg, 0.289 mmol) in DMF (2889 μl) was added TSTU (174 mg, 0.578mmol) followed by triethylamine (81 μl, 0.578 mmol). Stirred thereaction 1 hour. UPLC indicates formation of desired material UPLC-MSMethod C: Rt=0.99 min, m/z=568.2 [M+1]. This reagent (0.1M/DMF) was usedwithout further purification.

The dimers were prepared using either General Method B (Dimer 74) orGeneral Method C (Dimer 68). These dimers were characterized usingUPLC-MS Method D or UPLC-MS Method E, exhibiting either six charged,i.e. [(M+6)/6], (or seven charged, i.e. [(M+7)/7]) species of parentcompound at certain retention time (Rt). Dimer 68 was constructed usingLinker 33 and RHI. Dimer 74 was constructed using Linker 33 and Analog5. The results are shown in Table 13.

TABLE 13 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 68

A1, B1, A1′, B1′ = H 3.48 1993.09 74

A1, B1, A1′, B1′ = carbamoyl 3.56 1733.20 The wavy line indicates thebond between the epsilon amino group of the B29 Lys and B29′ Lys,repectively.

Example 27

The synthesis of Dimer 54 was as follows.

Dissolved A1-TFA-RHI (D. Liu et. al., Journal of Peptide Sci., 2012, 18,336-341) (100 mg, 0.017 mmol) in a pre-mixture containing water (5 mL)and potassium phosphate dibasic (24.49 mg, 0.141 mmol) (pH of resultingsolution is about 0.4). Added potassium cyanate (27.5 mg, 0.339 mmol)and stirred overnight. The product was purified by reverse-phasechromatography on C-8 phase (Column KROMASIL, C8 10 uM 100 A, size250×50 mm; solvent A=water/0.05% TFA, solvent B=AcCN/0.05% TFA), Flow=85mL/min, gradient B in A 26-34% in 30 min. UPLC-MS Method F: Rt=4.48 min,m/z=1486.9 [(M+4)/4+1].

Dissolved the above product (60 mg, 10.09 μmol) in DMSO (594 μl) andadded triethylamine (28.1 μl, 0.202 mmol) followed by solution of linkerdisuccinimidyl suberate (1.858 mg, 5.04 μmol) dissolved in 100 μL ofDMSO. Stirred for 3 hours. UPLC indicates reaction complete. Added thewhole reaction mixture into ammonium hydroxide (2105 μl, 15.13 mmol)(dropwise, exotherm expected). Stirred gently for 2 hours and confirmeddeprotection of the TFA group. Diluted the mixture by 20 mL of water andremoved most of ammonium hydroxide by diafiltration using 10K Amicontubes. Adjusted pH to about 3 and removed the salts by diafiltration.The product was purified by ion-exchange chromatography (PolySULFOETHYLA column, PolyLC Inc., 250×21 mm, 5 μm, 1000 Å; Buffer A: 0.1% (v/v)H₃PO₄/25% AcCN; Buffer B: 0.1% (v/v) H₃PO₄/25% AcCN/0.5 M NaCl). Theproduct was re-purified by reverse-phase chromatography on C-8 phase(Column KROMASIL, C8 10 μM 100 A, size 250×50 mm; solvent A=water/0.05%TFA, solvent B=AcCN/0.05% TFA). The result is shown below. Results areshown in Table 14.

TABLE 14 Insulin Type; (M + 6)/6 Dimer Structure of Dimer showing theLinking moiety Insulin Rt or No. between the B29 and B29′ Lysineresidues N termini (min) (M + 7)/7 54

RHI; A1, A1′ = H, B1, B1′ = carbamoyl 4.57 1974.45 The wavy lineindicates the bond between the epsilon amino group of the B29 Lys andB29′ Lys, respectively.

Example 28

Insulin Receptor Binding Assays were performed as follows.

IR binding assay was run in a scintillation proximity assay (SPA) in384-well format using cell membranes prepared from CHO cellsoverexpressing human IR(B) grown in F12 media containing 10% FBS andantibiotics (G418, Penicillin/Strepavidin). Cell membranes were preparedin 50 mM Tris buffer, pH 7.8 containing 5 mM MgCl₂. The assay buffercontained 50 mM Tris buffer, pH 7.5, 150 mM NaCl, 1 mM CaCl₂, 5 mMMgCl₂, 0.1% BSA and protease inhibitors (Complete-Mini-Roche). Cellmembranes were added to WGA PVT PEI SPA beads (5 mg/mL finalconcentration) followed by addition of insulin dimer molecules atappropriate concentrations. After 5-15 min incubation at roomtemperature, ¹²⁵[I]-insulin was added at 0.015 nM final concentrationfor a final total volume of 50 μL. The mixture was incubated withshaking at room temperature for 1 to 12 hours followed by scintillationcounting to determine ¹²⁵[I]-insulin binding to IR and the titrationeffects of insulin dimer molecules on this interaction.

Example 29

Insulin Receptor (IR) AKT-Phosphorylation Assays were performed asfollows.

IR AKT-Phosphorylation Assay: Insulin receptor activation can beassessed by measuring phosphorylation of the Akt protein, a key step inthe insulin receptor signaling cascade. CHO cell lines overexpressinghuman IR were utilized in an HTRF sandwich ELISA assay kit (Cisbio“Phospho-AKT(Ser473) and Phospho-AKT(Thr308) Cellular Assay Kits”).Cells were grown in F12 media supplemented with 10% FBS, 400 μg/mL G418and 10 mM HEPES. Prior to assay, the cells were incubated in serum freemedia for 2 to 4 hr. Alternatively, the cells could be frozen andaliquoted ahead of time in media containing 20% DMSO and used in theassay upon thawing, spin down and re-suspension. Cells were plated at10,000 cells per well in 20 μL of the serum free F12 media in 384-wellplates. Humulin and insulin glargine controls were run on each plate oftest compounds. The titrated compounds were added to the cells (2 μL perwell, final concentrations=1000 nM titrated down to 0.512 pM in 1:5 folddilutions) and incubated at 37° C. for 30 min. The cells were lysed with8 μL of the prepared lysis buffer provided in the CisBio kit andincubated at 25° C. for 1 hr. The diluted antibody reagents (anti-AKT-d2and anti-pAKT-Eu3/cryptate) were prepared according to the kitinstructions and then 10 μL was added to each well of cell lysatefollowed by incubation at 25° C. for 3.5 to 5 hr. The plate was read byin an Envision plate reader (Excitation=320 nm; Emission=665 nm) todetermine the IR pAkt agonist activity with regard to both potency andmaximum response for each compound. Alternatively, the compounds weretested in the same manner in the presence of 1.6 nM of Humulin todetermine how each compound was able to compete against the full agonistactivity of insulin.

Example 30

Table 15 shows the in vitro biological activity of the insulin dimerstowards the insulin receptor (IR). The activities were measured byeither ligand competition assays as described in EXAMPLE 28 orfunctional Akt-phosphorylation assays as described in Example 29.

TABLE 15 Dimer No. IR Binding IC₅₀ (nM) IR pAkt % Max 1 1.50 50.5 2 3.7733 3 1.38 59.5 4 1.62 47.5 5 2.42 43 6 1.00 83 7 3.19 60 8 7.15 47.5 93.29 42 10 3.59 34 11 1.37 32 12 13.1 41 13 2.51 36 14 4.42 38 15 2.5349 16 4.76 17 5.27 62 18 5.23 36 19 1.40 25 20 0.62 36 21 1.88 41 221.85 41.5 23 2.48 39 24 4.29 29.3 25 1.82 46 26 3.74 44 27 3.98 31 281.96 25 29 1.18 30 30 1.79 30 31 1.36 31 32 21.6 33 33 2.41 38 34 0.5767 35 1.17 66 36 0.53 28 37 3.52 42 38 2.18 45 39 3.17 45 40 2.03 41 410.64 35 42 2.97 49 43 2.02 35 44 1.18 33 45 4.00 38 46 0.38 25 47 4.5630 48 5.09 35 49 5.16 58 50 3.61 39 51 0.59 27 52 3.93 67 54 0.49 26 552.02 28 56 2.94 33 57 2.02 26 58 0.61 34 59 0.97 53 60 1.81 60 61 20.333 62 5.01 32 63 26.7 41 64 15.7 34 65 3.05 42 66 34.5 33 67 0.54 24 684.81 34 69 4.99 18 70 14.8 21 71 2.28 45 72 2.35 42 73 37.8 35 74 73.833 75 1.85 52 76 1.87 35 77 42.1 23 78 167 22 79 1.47 42 80 5.48 39 810.3 40 82 1.73 50 83 558 21 84 2.19 50

Example 31

In this example, in vivo effects of several insulin receptor partialagonists of the present invention were compared to Compound A (insulindimer MIU-90 disclosed in published PCT application No. WO2014052451)and compound B (B29,B29′-suberoyl-(insulin)₂) disclosed in Deppe et al.,Nauyn-Schmiedeberg's Arch. Pharmacol. 350: 213-217 (1994) but using RHIinstead of bovine insulin in an Intraperitoneal Insulin Tolerance Test(IP-ITT) assay performed in adult male, lean C57BL/6NTac mice.

Groups of N=6-8 animals per group were randomized by weight (averageabout 30 grams). Two days prior to study, the mice were conditioned todosing with an intraperitoneal injection of 0.9% Sodium Chloridesolution at 5 ml/kg dosing volume. On the morning of the study, food wasremoved two or four hours prior to the study. Blood glucoseconcentrations were determined at T=0 min (baseline) using a Glucometer.Mice were then dosed with vehicle, Dimer 24, Dimer 55, Dimer 58, Dimer60, Dimer 67, Compound A, Compound B, or Humulin (RHI) at 5 mL/kg viaintraperitoneal injection (see Table 16 for doses used). Blood glucoselevels were determined from tail bleeds taken between 30 to 360 minutesafter dose.

TABLE 16 Compound Doses A 72 nmol/Kg 300 nmol/Kg B 72 nmol/Kg 300nmol/Kg Dimer 24 72 nmol/Kg 300 nmol/Kg Dimer 55 120 nmol/Kg 300 nmol/KgDimer 58 60 nmol/Kg 300 nmol/Kg Dimer 60 120 nmol/Kg 300 nmol/Kg Dimer67 60 nmol/Kg 300 nmol/Kg Humulin 18 nmol/Kg 72 nmol/Kg

The results are shown in FIGS. 2A, 2B, 2C, 2D, 2E, 2F and 2G. Theresults show that the glucose profile for Dimer 24, Dimer 55, Dimer 58,Dimer 60, and Dimer 67 were substantially the same at both doses testedwhereas increasing the dosage of compounds A and B caused an increasedglucose lowering potency, indicating a lessor potential forhyperglycemic risk for the dimers compared to RHI or compounds A and B.

Example 32

The glucose lowering effect of Dimers 24, 18, and 40 were compared toRHI in Diabetic Yucatan miniature pigs (D minipigs) as follows.

Yucatan minipigs were rendered Type 1 diabetic by Alloxan injectionsfollowing a proprietary protocol developed by Sinclair Research Center(Auxvasse, Mo.). Induction is considered successful if basal glucoselevels exceed 150 mg/dL. D minipigs with plasma glucose levels ofapproximately 300 mg/dl were utilized in these experiments.

Male Yucatan minipigs, instrumented with two Jugular vein vascularaccess ports (VAP), were used in these studies. On the day of the studyafter an overnight fast, minipigs were placed in slings, and VAPs wereaccessed for infusion and sampling. At t=0 min, and after collecting twobaseline blood samples for plasma glucose measurement (t=−30 minutes andt=0 minutes), minipigs were administered Humulin (recombinant humaninsulin, RHI) or IRPA as a single bolus IV, at 0.69 nmol/kg. Humulin andIRPA were formulated at 69 nmol/ml in a buffer containing Glycerin, 16mg/mL; Metacresol, 1.6 mg/mL; Phenol, 0.65 mg/mL; Anhydrous SodiumPhosphate, Dibasic, 3.8 mg/mL; pH adjusted to 7.4 with HCl. Afterdosing, sampling continued for 480 minutes; time points for samplecollection were −30 min, 0 min, 8 min, 15 min, 30 min, 45 min, 60 min,90 min, 120 min, 150 min, 180 min, 210 min, 240 min, 270 min, 300 min,330 min, 360 min, 420 min, 480 min. Blood was collected in K3-EDTAtubes, supplemented with 10 μg/mL aprotinin, and kept on ice untilprocessing, which occurred within 30 minutes of collection. Aftercentrifugation at 3000 rpm, 4° C., for 8 min, plasma was collected andaliquoted for glucose measurement using a Beckman Coulter AU480Chemistry analyzer and for compound levels measurement.

FIG. 1 shows that at 0.69 nmol/kg concentration, RHI reduced serumglucose levels below 50 mg/dL whereas the insulin dimers did not. Thisresult shows that the insulin dimers present less risk of promotinghypoglycemia than RHI.

Example 33

The glucose lowering effect of Dimers 4, 5, 7, 8, 9, 18-29, 32, 37-41,43, 44, 48, 55, 57, 58, 60, 61, 62, 64, 67, 69, 71, 72, 77, and 78 werecompared to RHI in Diabetic Yucatan miniature pigs (D minipigs) asfollows.

Yucatan minipigs were rendered Type 1 diabetic by Alloxan injectionsfollowing a proprietary protocol developed by Sinclair Research Center(Auxvasse, Mo.). Induction is considered successful if basal glucoselevels exceed 150 D minipigs with plasma glucose levels of approximately300-400 mg/dl and instrumented with two Jugular vein vascular accessports (VAP), were used in these studies.

On the day of the study, after an overnight fast, minipigs were placedin slings, and VAPs were accessed for infusion and sampling. At t=0 min,and after collecting two baseline blood samples for plasma glucosemeasurement (t=−30 minutes and t=0 minutes), minipigs were administeredHumulin (recombinant human insulin, RHI) or other dimer as a singlebolus IV, at 0.69 nmol/Kg (0.35 nmol/kg for compound#78). Humulin anddimers were formulated at 69 nmol/mL in a buffer containing Glycerin, 16mg/mL; Metacresol, 1.6 mg/mL; Phenol, 0.65 mg/mL; Anhydrous SodiumPhosphate, Dibasic, 3.8 mg/mL, pH adjusted to 7.4 with HCl. Afterdosing, sampling continued for 480 minutes; time points for samplecollection were −30 minutes, 0 minutes, 8 minutes, 15 minutes, 30minutes, 45 minutes, 60 minutes, 90 minutes, 120 minutes, 150 minutes,180 minutes, 210 minutes, 240 minutes, 270 minutes, 300 minutes, 330minutes, 360 minutes, 420 minutes, and 480 minutes. Blood was collectedin K3-EDTA tubes, supplemented with 10 μg/mL aprotinin, and kept on iceuntil processing, which occurred within 30 minutes of collection. Aftercentrifugation at 3000 rpm, 4° C., for 8 minutes, plasma was collectedand aliquoted for glucose measurement using a Beckman Coulter AU480Chemistry analyzer. The results are shown FIG. 7A-7H. The Figures showthat at 0.69 nmol/kg concentration, RHI reduced serum glucose levelsbelow 50 mg/dL whereas the insulin dimers did not. This result showsthat the insulin dimers present less risk of promoting hypoglycemia thanRHI.

Example 34

This experiment compared the stability of the disulfide linking moietyof Compound A to the suberyol (C8) linking moiety of Dimer 24.

1 μM Compound A and Dimer 24 were each separately incubated in RatKidney Cell Membranes (RKCM) with or without 5 mM glutathione (GSH).Time 0 and Time 2 hour samples were obtained and the reaction quenchedwith 1 volume of 10% MeOH in AcCN with 0.1% Formic Acid. The quenchedsamples were then centrifuged and frozen prior to analysis. The sampleswere then thawed and analyzed using the Thermo Orbi Velos system.Targeted MetID analysis was performed with Extracted Ion Chromatograms(XICs) using 3 isotopes from 2 charge states at 10 ppm window.

Compound A metabolites were detected in RKCM both without GSH and withGSH. As shown in FIG. 3, monomer was about 1% of parent (stock solutionof Compound A) by 2 hours incubation. As shown in FIG. 4, monomer wasabout 6.5% of parent (stock solution of Compound A) by 2 hoursincubation. The results show the disulfide linkage was breaking overtime. No metabolites observed in 0 hour controls for Compound A or inthe stock solutions.

Dimer 24 produced metabolites that were detected in RKCM, however, whileloss of the A-chain polypeptide due to breakage of the disulfide bondsbetween the A-chain polypeptide and the B-chain polypeptide wasobserved, no monomers were detected. FIG. 5 shows that without GSH, lossof A-chain polypeptide was less thanl % of parent (stock solution ofDimer 24). FIG. 6 shows that with GSH, loss of A-chain polypeptide wasless thanl % of parent (stock solution of Dimer 24). No metabolitesobserved in 0 hour controls for Dimer 24 or in the stock solutions. Thenew quenching procedure with acidic conditions properly halted disulfideexchange.

Table of Sequences SEQ. ID NO: Description Sequence  1Homo sapiens insulin A chain GIVEQCCTSICSLYQLENYCN  2Homo sapiens insulin B chain FVNQHLCGSHLVEALYLVCGERGFFYTPKT  3Artificial sequence insulin A chain GX₂X₃EQCCX₈SICSLYQLX₁₇NX₁₉CX₂₃X₂ is isoleucine or threonine; X₃ is valine, glycine, or leucine;X₈ is threonine or histidine; X₁₇ is glutamic acid or glutamine;X₁₉ is tyrosine, 4-methoxy- phenylalanine, alanine, or 4-aminophenylalanine; X₂₃ is asparagine or glycine;  4Artificial sequence insulin B chainX₂₅LCGX₂₉X₃₀LVEALYLVCGERGFX₂₇YTX₃₁X₃₂ X₂₅ is histidine or threonine;X₂₉ is alanine, glycine or serine; X₃₀ is histidine, aspartic acid,glutamic acid, homocysteic acid, or cysteic acid;X₃₁ is proline or lysine; and X₃₂ is proline or lysine, with theproviso that at least one of X₃₁ or X₃₂ is lysine  5X₂₂ is phenylalanine or desamino- X₂₂VNQX₂₅X₂₆CGX₂₉X₃₀LVEALYLVCGERGFX₂₇Yphenylalanine; TX₃₁X₃₂X₃₃X₃₄X₃₅ X₂₅ is histidine or threonine;X₂₆ is glycine or leucine; X₂₇ is phenylalanine or aspartic acid;X₂₉ is alanine, glycine, or serine; X₃₀ is histidine, aspartic acid,glutamic acid, homocysteic acid, or cysteic acid;X₃₁ is aspartic acid, proline, or lysine; X₃₂ is lysine or proline;X₃₃ is threonine, alanine, or absent; X₃₄ is arginine or absent; andX₃₅ is arginine or absent; With the proviso at least one ofX₃₁ or X₃₂ is lysine  6 Artificial sequenceFVNQHLCGSHLVEALYLVCGERGFFYTKPT insulin lispro B chain  7Artificial sequence GIVEQCCTSICSLYQLENYCG insulin glargine A chain  8Artificial sequence FVNQHLCGSHLVEALYLVCGERGFFYTPKTRRInsulin glargine B chain  9 Artificial sequenceFVNQHLCGSHLVEALYLVCGERGFFYTDKT Insulin aspart B chain 10Artificial sequence FVNQHLCGSHLVEALYLVCGERGFFYTPK B: des30 11Artificial sequence GIVEQCCTSICSLYQLENACN A: Y19A

While the present invention is described herein with reference toillustrated embodiments, it should be understood that the invention isnot limited hereto. Those having ordinary skill in the art and access tothe teachings herein will recognize additional modifications andembodiments within the scope thereof. Therefore, the present inventionis limited only by the claims attached herein.

1-73. (canceled)
 74. A compound selected from the group consisting of

wherein the disulfide linkages between the Cys₆ and Cys₁₁ residues ofthe A-chain polypeptide and the disulfide linkages between the Cys₇ andCys₂₀ of the A-chain to the Cys₇ and Cys₁₉ of the B-chain polypeptide,respectively, are represented by the solid line therebetween; whereinthe linking moieties are covalently linked to the epsilon amino acid ofthe shown lysine residue, wherein the A-chain polypeptide for Dimers 71,72, 77 and 78 has the amino acid sequence shown in SEQ ID NO:1; and theB-chain polypeptide for Dimers 71, 72, 77 and 78 has the amino acidsequence shown in SEQ ID NO:2 respectively.
 75. A composition comprisingone or more compounds of claim 74 and a pharmaceutically acceptablecarrier.
 76. A method for treating diabetes comprising administering toan individual with diabetes a therapeutically effective amount of acomposition comprising the insulin receptor partial agonist of claim 75.77. The method of claim 76, wherein the diabetes is Type 1 diabetes,Type 2 diabetes, or gestational diabetes. 78-81. (canceled)
 82. Aninsulin dimer comprising: (a) a first B29 or B28 Lys of a first insulinheterodimer molecule having a first A-chain polypeptide and firstB-chain polypeptide and a second B29 or B28 Lys of a second insulinheterodimer having a second A-chain polypeptide and second B-chainpolypeptide conjugated together by a bifunctional linker selected fromthe group consisting of:

83-93. (canceled)
 94. A compound having the following formula